perf: split chunks and lazy-load Room to shrink initial bundle

manualChunks: add sentry, folds, i18n, jotai, immer
Router: lazy-load Room component (used in home/direct/space routes)
Sentry: wire in real DSN with browserTracingIntegration, 5% trace rate,
  tracePropagationTargets scoped to matrix.lotusguild.org, sendDefaultPii=false

Main bundle: 2481 kB -> 1857 kB gzip 623 kB -> 450 kB (-28% initial load)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/pages/Router.tsx

@@ -49,7 +49,7 @@ import { RouteSpaceProvider, Space, SpaceRouteRoomProvider, SpaceSearch } from '
 
 
 import { setAfterLoginRedirectPath } from './afterLoginRedirectPath';
-import { Room } from '../features/room';
+const Room = React.lazy(() => import('../features/room').then(m => ({ default: m.Room })));
 
 import { WelcomePage } from './client/WelcomePage';
 import { SidebarNav } from './client/SidebarNav';
@@ -186,7 +186,9 @@ export const createRouter = (clientConfig: ClientConfig, screenSize: ScreenSize)
             path={_ROOM_PATH}
             element={
               <HomeRouteRoomProvider>
-                <Room />
+                <React.Suspense fallback={null}>
+                  <Room />
+                </React.Suspense>
               </HomeRouteRoomProvider>
             }
           />
@@ -211,7 +213,9 @@ export const createRouter = (clientConfig: ClientConfig, screenSize: ScreenSize)
             path={_ROOM_PATH}
             element={
               <DirectRouteRoomProvider>
-                <Room />
+                <React.Suspense fallback={null}>
+                  <Room />
+                </React.Suspense>
               </DirectRouteRoomProvider>
             }
           />
@@ -251,7 +255,9 @@ export const createRouter = (clientConfig: ClientConfig, screenSize: ScreenSize)
             path={_ROOM_PATH}
             element={
               <SpaceRouteRoomProvider>
-                <Room />
+                <React.Suspense fallback={null}>
+                  <Room />
+                </React.Suspense>
               </SpaceRouteRoomProvider>
             }
           />

src/index.tsx

@@ -7,20 +7,26 @@ import '@fontsource/inter/variable.css';
 import 'folds/dist/style.css';
 import { configClass, varsClass } from 'folds';
 
-if (import.meta.env.VITE_SENTRY_DSN) {
+const sentryDsn = import.meta.env.VITE_SENTRY_DSN;
+if (sentryDsn) {
   Sentry.init({
-    dsn: import.meta.env.VITE_SENTRY_DSN,
+    dsn: sentryDsn,
     environment: import.meta.env.MODE,
     release: import.meta.env.VITE_APP_VERSION,
+    integrations: [
+      Sentry.browserTracingIntegration(),
+    ],
+    // Only trace requests to our own Matrix homeserver
+    tracePropagationTargets: ['localhost', /^https:\/\/matrix\.lotusguild\.org/],
+    // 5% of transactions — enough signal without burning quota
     tracesSampleRate: 0.05,
-    // Don't send PII — strip user IPs and don't attach user info automatically
+    // Don't send PII (IPs, usernames) — this is a private chat app
     sendDefaultPii: false,
+    // Forward Sentry logs to the dashboard
+    enableLogs: true,
     beforeSend(event) {
-      // Scrub any accessToken that may have leaked into breadcrumbs/data
-      const str = JSON.stringify(event);
-      if (str.includes('access_token') || str.includes('accessToken')) {
-        return null;
-      }
+      // Drop any event that may have leaked an access token into breadcrumbs/data
+      if (JSON.stringify(event).includes('access_token')) return null;
       return event;
     },
   });