feat: stateless federated identity resolver + federation UX improvements

Add identity.ts with isSelf() and resolveDisplayIdentity() — pure
stateless functions that detect replicated-self using the immutable
(username, homeInstance) composite key. No store lookups, no data
mutation. Fixes wrong avatar gradient and missing edit/delete on
own messages in remote channels.

Also includes: optimistic message dedup fix for cross-instance
messages (content-only matching), federation toast notifications,
Username component with @domain display, invite parser, and
deploy script simplification.

packages/web/src/stores/chatStore.ts

@@ -312,9 +312,12 @@ export const useChatStore = create<ChatState>((set, get) => ({
       const current = newMessages.get(channelId) ?? [];
       // Avoid duplicates
       if (current.find(m => m.id === message.id)) return state;
-      // Remove any optimistic temp message from same user with same content
+      // Remove any optimistic temp message with same content.
+      // Don't require userId match — for federated messages the home user ID
+      // differs from the replicated user ID, but content match is sufficient
+      // since temp messages are unique within the short optimistic window.
       const filtered = current.filter(m => {
-        if (!m.id.startsWith('temp_') || m.userId !== message.userId) return true;
+        if (!m.id.startsWith('temp_')) return true;
         return m.content !== message.content;
       });
       let updated = [...filtered, message];
@@ -333,9 +336,10 @@ export const useChatStore = create<ChatState>((set, get) => ({
       const current = newMessages.get(channelId) ?? [];
       // Avoid duplicates
       if (current.find(m => m.id === message.id)) return state;
-      // Remove any optimistic temp message from same user with same content
+      // Remove any optimistic temp message with same content (no userId check —
+      // federated messages arrive with a different replicated user ID)
       const filtered = current.filter(m => {
-        if (!m.id.startsWith('temp_') || m.userId !== message.userId) return true;
+        if (!m.id.startsWith('temp_')) return true;
         return m.content !== message.content;
       });
       let updated = [...filtered, message];

packages/web/src/stores/instanceStore.ts

@@ -91,6 +91,7 @@ interface InstanceState {
   connectToRemote: (origin: string, password: string, displayName?: string) => Promise<void>;
   loginToRemote: (origin: string, username: string, password: string) => Promise<void>;
   removeInstance: (origin: string) => void;
+  setInstanceStatus: (origin: string, status: ConnectedInstance['status'], error?: string) => void;
   syncInstanceList: () => Promise<void>;
   autoConnectAll: () => Promise<void>;
   reset: () => void;
@@ -276,6 +277,14 @@ export const useInstanceStore = create<InstanceState>((set, get) => ({
     }
   },
 
+  setInstanceStatus: (origin, status, error) => {
+    set((state) => ({
+      instances: state.instances.map(i =>
+        i.origin === origin ? { ...i, status, error } : i
+      ),
+    }));
+  },
+
   removeInstance: (origin: string) => {
     // Tear down WebSocket connection
     disconnectInstance(origin);

packages/web/src/stores/serverStore.ts

@@ -8,6 +8,16 @@ import { resolveAssetUrl, normalizeUserAssets } from '../utils/assetUrls';
 /** Server augmented with instance origin tracking (client-only, not in shared types). */
 export type TaggedServer = Server & { _instanceOrigin: string };
 
+// ─── Error types ─────────────────────────────────────────────────────────────
+
+/** Thrown when joinByCode targets a remote origin the user is not connected to. */
+export class NotConnectedError extends Error {
+  constructor(public origin: string) {
+    super(`Not connected to ${origin}`);
+    this.name = 'NotConnectedError';
+  }
+}
+
 // ─── Store interface ──────────────────────────────────────────────────────────
 
 interface ServerState {
@@ -41,7 +51,7 @@ interface ServerState {
   updateServer: (serverId: string, data: { name?: string; icon?: string }) => Promise<void>;
   deleteServer: (serverId: string) => Promise<void>;
   joinServer: (serverId: string, inviteCode: string) => Promise<void>;
-  joinByCode: (inviteCode: string) => Promise<Server>;
+  joinByCode: (inviteCode: string, origin?: string) => Promise<Server>;
   generateInvite: (serverId: string) => Promise<string>;
   createChannel: (serverId: string, name: string, type: 'text' | 'voice' | 'video', topic?: string) => Promise<Channel>;
   deleteChannel: (channelId: string) => Promise<void>;
@@ -182,7 +192,25 @@ export const useServerStore = create<ServerState>((set, get) => ({
     });
   },
 
-  joinByCode: async (inviteCode: string) => {
+  joinByCode: async (inviteCode: string, origin?: string) => {
+    if (origin) {
+      // Remote instance — verify connectivity via dynamic import (avoids circular dep)
+      const { useInstanceStore } = await import('./instanceStore');
+      const connected = useInstanceStore.getState().instances.some(
+        (i) => i.origin === origin && i.status === 'connected',
+      );
+      if (!connected) throw new NotConnectedError(origin);
+
+      const remoteApi = getApiForOrigin(origin);
+      const server = await remoteApi.servers.joinByCode(inviteCode);
+      set((state) => {
+        if (state.servers.find(s => s.id === server.id)) return state;
+        return { servers: [...state.servers, { ...server, _instanceOrigin: origin } as TaggedServer] };
+      });
+      return server;
+    }
+
+    // Home instance
     const server = await api.servers.joinByCode(inviteCode);
     set((state) => {
       if (state.servers.find(s => s.id === server.id)) return state;

packages/web/src/stores/uiStore.ts

@@ -15,6 +15,12 @@ type ModalType =
   | 'addDmMember'
   | null;
 
+interface Toast {
+  id: string;
+  message: string;
+  type: 'info' | 'warning' | 'success';
+}
+
 interface UIState {
   sidebarOpen: boolean;
   memberListOpen: boolean;
@@ -27,6 +33,7 @@ interface UIState {
     user: User | null;
     position: { top: number; left: number } | null;
   };
+  toasts: Toast[];
   toggleSidebar: () => void;
   toggleMemberList: () => void;
   openModal: (modal: ModalType, data?: Record<string, unknown>) => void;
@@ -37,6 +44,8 @@ interface UIState {
   closeImagePreview: () => void;
   openUserProfile: (user: User, position: { top: number; left: number }) => void;
   closeUserProfile: () => void;
+  addToast: (message: string, type?: 'info' | 'warning' | 'success', duration?: number) => void;
+  removeToast: (id: string) => void;
   voiceChatOpen: boolean;
   voiceFullscreen: boolean;
   pipCollapsed: boolean;
@@ -60,6 +69,7 @@ export const useUIStore = create<UIState>()(
         user: null,
         position: null,
       },
+      toasts: [],
 
       toggleSidebar: () => set((state) => ({ sidebarOpen: !state.sidebarOpen })),
       toggleMemberList: () => set((state) => ({ memberListOpen: !state.memberListOpen })),
@@ -91,6 +101,15 @@ export const useUIStore = create<UIState>()(
         userProfilePopout: { user: null, position: null }
       }),
 
+      addToast: (message, type = 'info', duration = 5000) => {
+        const id = Date.now().toString(36) + Math.random().toString(36).slice(2);
+        set((state) => ({ toasts: [...state.toasts, { id, message, type }] }));
+        setTimeout(() => {
+          set((state) => ({ toasts: state.toasts.filter(t => t.id !== id) }));
+        }, duration);
+      },
+      removeToast: (id) => set((state) => ({ toasts: state.toasts.filter(t => t.id !== id) })),
+
       voiceChatOpen: false,
       voiceFullscreen: false,
       pipCollapsed: false,