backspace/docs/systems/spaces.md

Space & Membership System

Source files:

• packages/server/src/routes/spaces.ts — Space CRUD, invite, join, members, roles, bans, ownership transfer, invite preview
• packages/server/src/routes/channels.ts — Channel CRUD, category CRUD, channel layout reordering, channel/category permission overrides
• packages/server/src/routes/explore.ts — Discovery listing, public join, join request workflow
• packages/server/src/routes/users.ts — Space layout (sidebar folders/ordering) persistence via PUT /api/users/@me/space-layout
• packages/web/src/stores/spaceStore.ts — Client-side space state, multi-instance merge, LWW layout sync
• packages/web/src/stores/exploreStore.ts — Explore page state, multi-instance discovery aggregation
• packages/web/src/components/modals/CreateSpace.tsx — Space creation modal (icon crop, color, visibility)
• packages/web/src/components/modals/JoinSpace.tsx — Join-by-code modal with federation connect phases
• packages/web/src/components/modals/InviteModal.tsx — Invite link generation and copy
• packages/web/src/components/modals/TransferOwnershipModal.tsx — Ownership transfer member picker
• packages/web/src/components/modals/SpaceSettings.tsx — Space settings: overview, discovery, members, roles, bans
• packages/web/src/components/JoinPage.tsx — Public invite landing page with federation redirect
• packages/web/src/hooks/useDragManager.ts — Channel/category/voice-user drag-and-drop
• packages/web/src/utils/inviteParser.ts — Invite code/URL/qualified-code parser

Cross-references: database.md (table schemas), permissions.md (resolution algorithm, override tiers), websocket.md (event types), federation.md (peer relay), voice.md (voice channel join)

---

Space Lifecycle

Creation

Endpoint: POST /api/spaces (spaces.ts:spaceRoutes) Auth: Required Permission: Any authenticated user

Request body (CreateSpaceRequest):

Field	Type	Required	Validation
name	string	yes	trimmed, 1-100 chars
icon	string	no	Upload filename
banner	string	no	Upload filename
avatarColor	AvatarColor	no	Must be in AVATAR_COLORS; random if omitted
visibility	SpaceVisibility	no	'public' / 'request' / 'private'; defaults to 'private'
description	string	no	trimmed, max 200 chars

AVATAR_COLORS: ['mint', 'sky', 'lavender', 'coral', 'rose', 'teal', 'amber']

Atomic transaction creates:

Entity	ID	Details
Space	spaceId (snowflake)	With inviteCode = crypto.randomBytes(4).toString('hex') (8 hex chars)
Owner membership	(spaceId, userId)	Creator auto-joined
Category: "text-channels"	textCategoryId (snowflake)	position 0
Category: "voice-channels"	voiceCategoryId (snowflake)	position 1
Channel: "general" (text)	channelId (snowflake)	position 0, in text-channels category
Channel: "voice" (voice)	voiceChannelId (snowflake)	position 0, in voice-channels category
@everyone role	id = spaceId	DEFAULT_EVERYONE_PERMISSIONS, position 0, color #b9bbbe

DEFAULT_EVERYONE_PERMISSIONS bits: VIEW_CHANNEL, SEND_MESSAGES, CREATE_INVITE, CONNECT, SPEAK, ATTACH_FILES, READ_MESSAGE_HISTORY, ADD_REACTIONS, STREAM

Post-transaction:

1. connectionManager.addUserSpace(userId, spaceId) — registers creator for WS broadcasts
2. Icon/banner attachment records cleaned up (reference now in spaces table)
3. Icon/banner resized via resizeProfileImage(filePath, 'icon'|'banner')

Response: 201, Space object

Read

List user's spaces: GET /api/spaces — returns all spaces where user is a member. Response: Space[].

Get space detail: GET /api/spaces/:id — membership required. Returns SpaceWithChannelsAndMembers:

• Channels filtered by VIEW_CHANNEL permission per-channel (computed per-user)
• Each channel includes isPrivate (true if @everyone has VIEW_CHANNEL deny override) and myPermissions
• Categories include isPrivate flag
• Roles include permissions field only if requesting user has MANAGE_ROLES
• myPermissions at space level included

Update

Endpoint: PATCH /api/spaces/:id Permission: MANAGE_SPACE

Updatable fields: name (1-100 chars), icon, banner, avatarColor (validated against AVATAR_COLORS), visibility (public/request/private), description (max 200 chars).

Side effects:

• Old icon/banner files deleted from disk when replaced
• New icon/banner resized via resizeProfileImage
• Attachment records cleaned up for newly-set images
• space_updated WS event broadcast to all space members

Delete

Endpoint: DELETE /api/spaces/:id Permission: Owner only (isSpaceOwner check)

Transaction deletes (in order):

1. read_states for all channels in the space (no FK cascade)
2. All channels (messages cascade via FK)
3. All space_members
4. All space_folder_members referencing this space
5. The space itself

Post-transaction: All attachment files and space icon/banner files deleted from disk.

---

Invite System

Invite Code Generation

Endpoint: POST /api/spaces/:id/invite Permission: CREATE_INVITE

Behavior: Returns existing inviteCode if one exists. Only generates a new one (crypto.randomBytes(4).toString('hex')) if the space has no invite code. Invite codes are permanent (no expiration).

Response: { inviteCode: string }

Invite URL Format

Generated by InviteModal.tsx:

• Web: {instanceOrigin}/join/{inviteCode} (e.g., https://nova.ddns.net/join/a3f1b2c4)
• Deep link (Electron): backspace://join/{inviteCode} or backspace://join/{inviteCode}@{host} for remote instances

Invite Code Parser (inviteParser.ts)

Parses three input formats into { code: string; origin?: string }:

Format	Example	Parsed
Bare code	a3f1b2c4	{ code: 'a3f1b2c4' }
Full URL	https://remote.com/join/a3f1b2c4	{ code: 'a3f1b2c4', origin: 'https://remote.com' }
Qualified code	a3f1b2c4@remote.com	{ code: 'a3f1b2c4', origin: 'https://remote.com' }

If the parsed origin matches window.location.origin, it is treated as a bare code (origin stripped).

Invite Preview

Endpoint: GET /api/spaces/invite/:code/preview (no auth required)

Response (InvitePreview):

{
  spaceId: string;
  spaceName: string;
  description: string | null;
  icon: string | null;
  avatarColor: AvatarColor | null;
  memberCount: number;     // live count from space_members
  instanceName: string;    // from instance_settings
}

Join by Invite Code

Two endpoints serve the same purpose:

Endpoint	Use case
POST /api/spaces/:id/join	Join when spaceId is known (body: { inviteCode })
POST /api/spaces/join	Join by code only, spaceId looked up from inviteCode

Validations: invite code match, not banned, not already a member.

Side effects:

1. Insert space_members row
2. connectionManager.addUserSpace for WS broadcasts
3. member_joined WS event broadcast to space
4. Response: Space object

Join Page (JoinPage.tsx)

Public route at /join/:inviteCode. Handles five phases:

Phase	Trigger	UI
preview	Initial load	Space preview card + join button (auth) or login/register links (unauth)
connect	NotConnectedError on join attempt	Password prompt for federation connect
fallback	DifferentPasswordError on connect	Username + password for existing remote account
other-instance	User clicks "I use another instance"	Domain input for federation redirect
already-member	Join returns "already a member"	Green checkmark + auto-redirect (2s timer)

Federation redirect flow (other-instance):

1. User enters their home domain (e.g., my-instance.com)
2. Constructs qualified invite: {code}@{currentHost}
3. Redirects to https://{domain}/join/{qualifiedCode}
4. Their home instance's JoinPage receives the qualified code, parses origin, and handles federation connect

Preview fetching: For remote invites, creates a temporary API client via createApiClient(origin, () => null) to fetch the preview without authentication.

Join Space Modal (JoinSpaceModal)

Modal with three phases matching JoinPage but in-app:

• input — text field for invite code or URL
• connect — password prompt for federation
• fallback — different-password login for remote instance

Uses parseInviteInput to parse, then joinByCode(code, origin?) from spaceStore.

---

Discovery System

Space Visibility

Value	Explore listing	Join mechanism
private	Not listed	Invite code only
request	Listed	Submit join request, requires approval
public	Listed	Instant join, no invite needed

Explore Endpoint

Endpoint: GET /api/spaces/explore (explore.ts:exploreRoutes) Auth: Required Query params: q (search), limit (1-100, default 50), offset (default 0)

Instance-level gate: Checks instance_settings.discoveryEnabled. If false, returns { spaces: [], total: 0, discoveryEnabled: false }.

Query: Raw SQL with LEFT JOIN on space_members for member count. Filters to visibility IN ('public', 'request'). Search matches name or description (LIKE, case-insensitive). Ordered by member_count DESC, created_at DESC.

Response (ExploreSpace[]):

{
  id: string;
  name: string;
  icon: string | null;
  banner: string | null;
  avatarColor: AvatarColor | null;
  description: string | null;
  visibility: 'public' | 'request';
  memberCount: number;
  createdAt: number;
  joined: boolean;         // true if requesting user is already a member
}

Also returns total (filtered count), totalAll (all discoverable), discoveryEnabled.

Multi-Instance Discovery (exploreStore.ts)

fetchSpaces() queries home + all connected remote instances in parallel:

1. Waits for instanceStore._autoConnectDone to avoid querying with incomplete instance list
2. Promise.allSettled across home API + all connected instance APIs
3. Deduplicates by spaceId:origin key
4. Normalizes remote asset URLs via resolveAssetUrl
5. Merges into TaggedExploreSpace[] with _instanceOrigin

Public Join

Endpoint: POST /api/spaces/:id/public-join Validation: Space must have visibility === 'public', not banned, not already member.

Side effects: Same as invite join (insert member, WS broadcast, add to connectionManager). Response: Full SpaceWithChannelsAndMembers (not just Space), so the client can immediately populate the store without a follow-up GET /api/spaces/:id.

Join Request Workflow

Submit request: POST /api/spaces/:id/request-join

• Space must have visibility === 'request'
• Rate limited: 5 per minute
• Message: optional, max 500 chars
• Checks for existing pending request (409 if exists)
• Creates join_requests row with status 'pending'
• Sends join_request_received WS event to all space managers (owner + MANAGE_SPACE holders)

List requests: GET /api/spaces/:id/join-requests?status=pending

• Permission: owner or MANAGE_SPACE
• Status filter: pending (default), accepted, declined
• Returns { requests: JoinRequest[] } with populated user data

Decide request: PATCH /api/spaces/:id/join-requests/:requestId

• Permission: owner or MANAGE_SPACE
• Body: { action: 'accept' | 'decline' }
• Must be pending (400 if already decided)

Accept flow (atomic transaction):

1. Insert space_members row
2. Update request status to 'accepted', set decidedBy and decidedAt
3. connectionManager.addUserSpace
4. Broadcast member_joined to space
5. Build full SpaceWithChannelsAndMembers for accepted user
6. Send join_request_accepted WS event to requesting user (includes full space data)

Decline flow:

1. Update request status to 'declined'
2. Send join_request_declined WS event to requesting user

User's own requests: GET /api/users/@me/join-requests?status=<optional>

• Returns all requests for the current user, optionally filtered by status

Space Managers Resolution (explore.ts:getSpaceManagers)

Used to target join_request_received events. Iterates all space members and returns IDs where:

• userId === space.ownerId, OR
• hasPermission(userId, spaceId, PermissionBits.MANAGE_SPACE) returns true

---

Membership

Join

Three join paths:

1. Invite code — POST /api/spaces/:id/join or POST /api/spaces/join
2. Public join — POST /api/spaces/:id/public-join (visibility=public)
3. Request accept — PATCH /api/spaces/:id/join-requests/:requestId with action: 'accept'

All paths: insert space_members, register in connectionManager, broadcast member_joined.

Leave / Kick

Endpoint: DELETE /api/spaces/:id/members/:uid

Scenario	Condition	Permission
Self-leave	uid === request.userId	Any member (unless owner)
Kick	uid !== request.userId	KICK_MEMBERS

Owner restriction: Owner cannot leave. Must transfer ownership or delete the space. Owner protection: Cannot kick the owner.

Cleanup on removal:

1. Delete space_members row
2. Delete voice_restrictions for the member in this space
3. Delete read_states for the member in all space channels
4. Broadcast member_left WS event

Ban

Endpoint: POST /api/spaces/:id/bans Permission: BAN_MEMBERS Body: { userId: string, reason?: string }

Protections: Cannot ban owner, cannot ban self, 409 if already banned.

Atomic transaction:

1. Insert bans row (with reason, bannedBy, createdAt)
2. Delete space_members
3. Delete member_roles
4. Delete read_states for all space channels
5. Delete voice_restrictions

WS events:

• member_left to space (so other members update their list)
• member_banned to the banned user (with reason)

List bans: GET /api/spaces/:id/bans — requires BAN_MEMBERS. Returns ban records with both banned user and moderator user objects.

Unban: DELETE /api/spaces/:id/bans/:uid — requires BAN_MEMBERS. 404 if no ban found.

Ownership Transfer

Endpoint: PATCH /api/spaces/:id/transfer-ownership Permission: Owner only Body: { newOwnerId: string } Validation: New owner must be a member, cannot transfer to self.

Updates spaces.ownerId, broadcasts space_updated WS event.

Client (TransferOwnershipModal): Member picker with search, two-step confirm. Shows warning "You will become a regular member." Uses toast notification on success.

Member Role Management

Set roles (replace): PATCH /api/spaces/:id/members/:uid

• Permission: MANAGE_ROLES
• Body: { roleIds: string[] }
• Cannot change own roles
• Cannot modify owner's roles (unless you are the owner)
• @everyone role (id=spaceId) cannot be assigned
• Atomically deletes all existing member_roles then inserts new ones
• Triggers connectionManager.pushReadyPayload(uid) to force re-sync
• Triggers checkVoicePermissions(spaceId) to enforce voice changes

Add single role: POST /api/spaces/:id/members/:uid/roles — body { roleId }, requires MANAGE_ROLES

Remove single role: DELETE /api/spaces/:id/members/:uid/roles/:roleId — requires MANAGE_ROLES

---

Role Management

Create Role

Endpoint: POST /api/spaces/:id/roles Permission: MANAGE_ROLES Body: { name: string, color?: string, permissions?: string }

• Name defaults to 'new role' if empty
• Duplicate name check (case-insensitive, raw SQL COLLATE NOCASE)
• Permissions default to DEFAULT_EVERYONE_PERMISSIONS if not provided
• Position defaults to 0
• Color defaults to '#b9bbbe'
• After creation: pushes ready payload to all space members, checks voice permissions

Update Role

Endpoint: PATCH /api/spaces/:id/roles/:roleId Permission: MANAGE_ROLES Body: { name?, color?, position?, permissions? }

• Name: trimmed, non-empty, duplicate check (case-insensitive, excludes self)
• Permissions: validated as valid bigint string
• After update: pushes ready payload to all members, checks voice permissions

Delete Role

Endpoint: DELETE /api/spaces/:id/roles/:roleId Permission: MANAGE_ROLES

• Cannot delete @everyone role (roleId === spaceId)
• Deletes channel overrides referencing this role
• After delete: pushes ready payload to all members, checks voice permissions

---

Channel Management

Channel Types

Type	Semantics
text	Message-based channel with read states, embeds, reactions
voice	Voice/video channel (LiveKit integration, see voice.md)

Create Channel

Endpoint: POST /api/spaces/:id/channels Permission: MANAGE_CHANNELS

Field	Validation
name	Required, trimmed, lowercased, spaces→hyphens, 1-100 chars
type	Required, 'text' or 'voice'
topic	Optional, trimmed
categoryId	Optional, validated against space's categories

Position: max(existing positions) + 1.

Broadcast: channel_created sent per-user (only to users with VIEW_CHANNEL on the new channel). Each user's event includes their computed myPermissions.

Update Channel

Endpoint: PATCH /api/channels/:id Permission: MANAGE_CHANNELS (checked with channel-level override context) Body: { name?, topic?, position?, categoryId? }

• Name: same normalization as create
• Position: non-negative number
• categoryId: null to unassign, or valid category ID in same space

Broadcast behavior:

• If categoryId changed: calls broadcastOverrideChange (per-user VIEW_CHANNEL recheck, may send channel_deleted to users who lost access)
• Otherwise: simple channel_updated broadcast to channel viewers

Delete Channel

Endpoint: DELETE /api/channels/:id Permission: MANAGE_CHANNELS

Cleanup sequence:

1. Disconnect all voice participants (if voice channel)
2. Collect viewer IDs before deletion (for targeted broadcast)
3. Collect attachment filenames before cascade
4. Delete read_states (no FK)
5. Delete messages (attachments cascade)
6. Delete channels row
7. Delete attachment files from disk
8. Broadcast channel_deleted only to users who could see the channel

Category Management

Create: POST /api/spaces/:id/categories — permission: MANAGE_CHANNELS, name 1-100 chars, auto-position. Broadcasts category_created.

Update: PATCH /api/categories/:id — permission: MANAGE_CHANNELS, updatable: name, position. Broadcasts category_updated (includes isPrivate flag).

Delete: DELETE /api/categories/:id — permission: MANAGE_CHANNELS. Transaction nulls categoryId on child channels, then deletes category. Broadcasts category_deleted then channel_layout_updated (per-user filtered).

Channel Layout Reorder

Endpoint: PATCH /api/spaces/:id/channel-layout Permission: MANAGE_CHANNELS

Body:

{
  channels: Array<{ id: string; position: number; categoryId: string | null }>;
  categories: Array<{ id: string; position: number }>;
}

Validation:

• All channel IDs must belong to the space
• All category IDs must belong to the space
• All positions must be non-negative numbers
• Channel categoryId references must point to valid space categories

Applied atomically in a transaction. Broadcasts via broadcastChannelLayout() which sends channel_layout_updated per-user (each user sees only channels they have VIEW_CHANNEL on).

Channel/Category Permission Overrides

OUT OF SCOPE for this document. See permissions.md for the three-tier override system (category overrides, channel overrides, member overrides) and the computePermissions algorithm.

Override endpoints documented here for API completeness:

Endpoint	Permission	Notes
GET /api/channels/:id/overrides	MANAGE_ROLES	List channel overrides
PUT /api/channels/:id/overrides	MANAGE_ROLES	Upsert (delete+insert in tx). Privilege escalation guard.
DELETE /api/channels/:id/overrides/:targetType/:targetId	MANAGE_ROLES	Remove override
GET /api/categories/:id/overrides	MANAGE_ROLES	List category overrides
PUT /api/categories/:id/overrides	MANAGE_ROLES	Upsert with escalation guard
DELETE /api/categories/:id/overrides/:targetType/:targetId	MANAGE_ROLES	Remove override

All override mutations call broadcastOverrideChange (channel) or broadcastCategoryOverrideChange (category) which re-evaluates VIEW_CHANNEL per-user and sends channel_updated (gained access) or channel_deleted (lost access). Voice permission enforcement via checkVoicePermissions runs after every override change.

Drag-and-Drop (useDragManager.ts)

Client-side hook managing three drag types:

Type	Draggable	Drop target	Permission
channel	Channel items	Before/after channels or categories	MANAGE_CHANNELS (canManage)
category	Category headers	Before/after channels or categories	MANAGE_CHANNELS (canManage)
voiceUser	Voice participant	Different voice channel	MOVE_MEMBERS (canMoveMembers)

Drop position normalization: "before B" is normalized to "after A" (the preceding item in orderedItems) to prevent double drop-indicator rendering.

Auto-scroll: When dragging near top/bottom edges (40px), scrolls the sidebar container proportionally to edge distance.

Self-drop guard: Dropping on the same item is a no-op.

---

Space Layout (Sidebar Ordering & Folders)

Data Model

Layout items (SpaceLayoutItem):

type SpaceLayoutItem =
  | { t: 's'; id: string }   // space reference
  | { t: 'f'; id: string };  // folder reference

Folders (SpaceFolder):

interface SpaceFolder {
  id: string;
  userId: string;
  name: string | null;
  color: string | null;
  position: number;
  spaceIds: string[];   // ordered list of spaces in the folder
}

Server Persistence

Tables (see database.md): user_space_layout, space_folders, space_folder_members

Endpoint: PUT /api/users/@me/space-layout (users.ts)

Request body:

{
  items: SpaceLayoutItem[];
  folders: Record<string, {
    name: string | null;
    color: string | null;
    spaceIds: string[];
  }>;
  updatedAt?: number;   // LWW timestamp
}

Server-generated folder IDs: Clients use new:* prefixed keys for new folders. The server maps each new:* key to a generateSnowflake() ID. The response returns resolved IDs so the client can update references.

Remote folder adoption: If a folder ID does not match an existing folder and does not start with new:, the server creates it with the provided ID (handles folders created on another instance being pushed to this one).

Transaction:

1. For each folder in request: create new / update existing / adopt remote
2. Clear and re-insert space_folder_members with ordered positions
3. Delete folders not in request (with their members)
4. Replace new:* keys in items array with resolved IDs
5. Upsert user_space_layout row (JSON string of items)

WS broadcast: space_layout_updated sent to the user's other connections (multi-tab sync).

Response: { items, folders, updatedAt }

LWW Conflict Resolution

Server-side guard (users.ts): If the request includes updatedAt and it is older than the stored updatedAt, the write is rejected and the current layout is returned without modification.

Client-side algorithm (spaceStore.ts:populateFromReady):

On receiving ready payload from any instance:
  incomingTs = payload.layoutUpdatedAt ?? 0
  currentTs = store._layoutUpdatedAt

  if incomingTs >= currentTs:
    Accept incoming layout (overwrite local)
    _layoutUpdatedAt = incomingTs
  else:
    Keep local layout
    Push local layout to the stale instance via pushLayoutToOrigin()

pushLayoutToOrigin(origin, layout, folders, updatedAt): Calls targetApi.spaceLayout.update() on the specific instance that had the stale layout. This ensures all instances converge to the newest layout.

Multi-Instance Layout Push

updateSpaceLayout(items, folders) in spaceStore:

1. Optimistically applies the layout with Date.now() timestamp
2. Collects all targets: home API + all connected remote instance APIs
3. Promise.allSettled pushes to all targets in parallel
4. Uses the first successful response to resolve new:* folder IDs
5. Updates store with resolved layout

---

WS Ready Payload

The space layout and folder data are delivered in the WS ready event (handler.ts:buildReadyPayload):

{
  spaces: SpaceWithChannelsAndMembers[];
  folders: SpaceFolder[];
  spaceLayout: SpaceLayoutItem[] | null;
  layoutUpdatedAt: number | null;
  dmChannels: DmChannel[];
  // ... other fields
}

populateFromReady merges incoming data by origin:

• Replaces all spaces from the incoming origin, keeps spaces from other origins
• Populates channelToSpaceMap, channelOriginMap, channelPermissions, voiceChannelIds, categoryOriginMap
• DM channels: removes existing DMs from this origin, appends incoming, deduplicates 1-on-1 DMs by canonical member pair (prefers home-origin copy)
• Applies LWW layout merge as described above

---

WS Events Summary

Event	Direction	Trigger
space_updated	S→C (space)	Space metadata changed
member_joined	S→C (space)	New member via any join path
member_left	S→C (space)	Member left, kicked, or banned
member_banned	S→C (user)	Sent to the banned user with reason
join_request_received	S→C (user)	Sent to space managers when request submitted
join_request_accepted	S→C (user)	Sent to requester with full space data
join_request_declined	S→C (user)	Sent to requester
channel_created	S→C (per-user)	New channel, per-user VIEW_CHANNEL filter
channel_updated	S→C (per-user/channel)	Channel or override changed
channel_deleted	S→C (per-user)	Channel deleted or user lost VIEW_CHANNEL
category_created	S→C (space)	New category
category_updated	S→C (space)	Category name/position/privacy changed
category_deleted	S→C (space)	Category removed
channel_layout_updated	S→C (per-user)	Batch reorder, per-user channel filtering
space_layout_updated	S→C (user)	Sidebar layout changed (multi-tab sync)

---

Federation Considerations

Instance Origin Tagging

Every space in the client store has _instanceOrigin: string:

• '' (empty) = home instance
• 'https://remote.com' = remote federated instance

All store actions resolve the correct API client via getApiForOrigin(origin) before making HTTP requests. The resolver is registered by instanceStore on import (breaks circular dependency).

User ID Resolution

getMyUserIdForOrigin(origin) returns the user's ID on a specific instance:

• Home (''): returns authStore.user.id
• Remote: checks _myUserIdByOrigin cache (populated from WS ready events), falls back to instanceStore resolver

Used for self-leave (leaveSpace calls removeMember with the correct user ID for the instance).

Remote Invite Join Flow

1. User enters invite URL pointing to remote instance
2. parseInviteInput extracts code + origin
3. joinByCode(code, origin) called
4. If not connected → NotConnectedError thrown
5. JoinSpaceModal/JoinPage enters 'connect' phase
6. User provides password → connectToRemote(origin, password)
7. If password mismatch → DifferentPasswordError → 'fallback' phase
8. On success: joinByCode retried, space added to store with _instanceOrigin

Asset URL Normalization

Remote space icons, banners, and member avatars are resolved via resolveAssetUrl(path, origin) when:

• populateFromReady processes spaces from a remote origin
• loadSpaceDetail loads a remote space
• joinByCode returns a remote space
• exploreStore.fetchSpaces processes remote explore results