feat(voice): add real-time voice room with LiveKit

- LiveKit WebRTC SFU container in docker-compose
- Voice token microservice (Node.js + Express)
- VoiceRoom page with member grid and controls
- useVoiceRoom composable for LiveKit connection
- Voice entry button in TeamSessionPanel
- Nginx proxy for voice-token service API

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/router/index.ts

@@ -54,6 +54,13 @@ const routes: RouteRecordRaw[] = [
         props: true,
         meta: { requiresAuth: true }
       },
+      {
+        path: 'group/:groupId/voice/:sessionId',
+        name: 'VoiceRoom',
+        component: () => import('@/views/VoiceRoom.vue'),
+        props: true,
+        meta: { requiresAuth: true }
+      },
       {
         path: 'games',
         name: 'GamesLibrary',