perf: Redis pub/sub, PgBouncer, optimistic UI for high concurrency

- Add Redis 7 for pub/sub (lobby + chat real-time), rate limiting, caching
- Replace SSE DB polling with Redis pub/sub (lobby: instant approval, chat: instant delivery)
- Add PgBouncer (transaction mode, 500 client → 25 pool connections)
- Chat SSE stream via Redis pub/sub instead of 3s polling
- Optimistic UI in ChatPanel (messages appear before server confirms)
- Redis-based rate limiter (works across multiple app replicas)
- Prisma query optimization (select only needed fields)
- Chat message cache in Redis (10s TTL)
- Docker Compose: add redis, pgbouncer services with healthchecks
- Production: resource limits, 2 app replicas behind Traefik
- Update CLAUDE.md, README.md, .env.example, setup.sh

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

README.md

@@ -9,7 +9,8 @@
 - **Backend:** Next.js Route Handlers, `livekit-server-sdk`
 - **Auth:** `better-auth` + Prisma adapter
 - **AI Agent:** Python, `livekit-agents`, Deepgram STT, OpenAI GPT
-- **DB:** PostgreSQL + Prisma 7
+- **DB:** PostgreSQL + Prisma 7 + PgBouncer (connection pooling)
+- **Cache/PubSub:** Redis 7 (real-time chat, lobby, rate limiting)
 - **Storage:** MinIO (S3-compatible)
 - **Proxy:** Traefik v3 + Let's Encrypt (production)
 
@@ -53,10 +54,10 @@ cp .env.example .env
 ### 3. Запустить базу данных
 
 ```bash
-docker compose up -d postgres minio
+docker compose up -d postgres minio redis
 ```
 
-Поднимет PostgreSQL на `localhost:5432` и MinIO на `localhost:9000` (консоль: `localhost:9001`).
+Поднимет PostgreSQL (`localhost:5432`), MinIO (`localhost:9000`, консоль: `9001`), Redis (`localhost:6379`), PgBouncer (`localhost:6432`).
 
 ### 4. Применить миграции