fix: repair invite links, social features, messaging + Discord UI overhaul

Phase 1 - Feature Repair:
- Fix member kick/leave: add missing db.delete() call in servers.ts
- Stabilize invite codes: return existing code instead of regenerating
- Fix user search: use LIKE instead of exact match in social.ts
- Wire DM button on FriendsPage to create/navigate to DM channels
- Add cancel outgoing friend request (DELETE endpoint + frontend)
- Add accept/decline friend request actions with WS real-time events
- Fix replyToId persistence in message creation
- Hydrate reactions and replyTo in message queries
- Add joinByCode to API client and serverStore
- Add friend_request_received/accepted WebSocket events

Phase 2 - Discord UI Overhaul:
- Remove stray borders between layout columns
- Replace shadow-sm with shadow-header on content headers
- Replace all bg-gray-*/text-gray-* with Discord color tokens
- Ensure flat color contrast (#1E1F22, #2B2D31, #313338)

Testing:
- Set up vitest + @testing-library/react + jsdom
- Add 17 tests across InviteModal, JoinServer, FriendsPage (all passing)
- Fix vite resolve.extensions to prefer .tsx over stale .js files

packages/web/src/stores/voiceStore.ts

@@ -1,4 +1,5 @@
 import { create } from 'zustand';
+import type { ParticipantInfo } from '../hooks/useLiveKit';
 
 interface VoiceState {
   voiceUsers: Map<string, string[]>; // channelId → userIds
@@ -7,14 +8,16 @@ interface VoiceState {
   isDeafened: boolean;
   isCameraOn: boolean;
   isScreenSharing: boolean;
+  participants: ParticipantInfo[];
   setVoiceUsers: (channelId: string, userIds: string[]) => void;
   addVoiceUser: (channelId: string, userId: string) => void;
   removeVoiceUser: (channelId: string, userId: string) => void;
   setCurrentVoiceChannel: (channelId: string | null) => void;
-  toggleMute: () => void;
-  toggleDeafen: () => void;
+  setParticipants: (participants: ParticipantInfo[]) => void;
+  toggleMic: () => void;
   toggleCamera: () => void;
   toggleScreenShare: () => void;
+  toggleDeafen: () => void;
   getVoiceUsers: (channelId: string) => string[];
   reset: () => void;
 }
@@ -26,6 +29,7 @@ export const useVoiceStore = create<VoiceState>((set, get) => ({
   isDeafened: false,
   isCameraOn: false,
   isScreenSharing: false,
+  participants: [],
 
   setVoiceUsers: (channelId, userIds) => {
     set((state) => {
@@ -57,7 +61,9 @@ export const useVoiceStore = create<VoiceState>((set, get) => ({
 
   setCurrentVoiceChannel: (channelId) => set({ currentVoiceChannelId: channelId }),
 
-  toggleMute: () => set((state) => ({ isMuted: !state.isMuted })),
+  setParticipants: (participants) => set({ participants }),
+
+  toggleMic: () => set((state) => ({ isMuted: !state.isMuted })),
   toggleDeafen: () => set((state) => ({ isDeafened: !state.isDeafened })),
   toggleCamera: () => set((state) => ({ isCameraOn: !state.isCameraOn })),
   toggleScreenShare: () => set((state) => ({ isScreenSharing: !state.isScreenSharing })),