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/vite.config.ts

@@ -1,10 +1,18 @@
+/// <reference types="vitest" />
 import { defineConfig } from 'vite';
 import react from '@vitejs/plugin-react';
 import path from 'path';
 
 export default defineConfig({
   plugins: [react()],
+  test: {
+    globals: true,
+    environment: 'jsdom',
+    setupFiles: ['./src/test/setup.ts'],
+    css: false,
+  },
   resolve: {
+    extensions: ['.tsx', '.ts', '.jsx', '.js', '.mjs', '.mts', '.json'],
     alias: {
       '@': path.resolve(__dirname, './src'),
     },
@@ -13,11 +21,11 @@ export default defineConfig({
     port: 5173,
     proxy: {
       '/api': {
-        target: 'http://localhost:3000',
+        target: 'http://localhost:3005',
         changeOrigin: true,
       },
       '/ws': {
-        target: 'ws://localhost:3000',
+        target: 'ws://localhost:3005',
         ws: true,
       },
     },