feat(ws): implement WebSocket cluster mode with Redis Pub/Sub

Introduce a new WebSocket messaging architecture that supports both standalone and cluster modes. This allows for horizontal scaling of WebSocket servers by using Redis Pub/Sub to synchronize messages across multiple instances.

Key changes:
- Added `ws.MessagePublisher` interface to abstract message distribution.
- Implemented `ws.Bus` to handle cluster-mode messaging via Redis.
- Added `ws.OnlineTracker` to manage user online status across the cluster.
- Refactored multiple services (Chat, Group, Push, Call, etc.) to use the new `MessagePublisher` instead of a concrete `ws.Hub`.
- Added WebSocket configuration options (mode, instance ID, channel, TTL, heartbeat) to `config.yaml` and `config.go`.
- Updated dependency injection with Wire to support the new publisher and Redis client.
- Improved logging by replacing standard `log` with `zap` in several service components.

configs/config.yaml

@@ -277,3 +277,16 @@ jpush:
 # 设置后可使用 POST /api/v1/admin/setup-super-admin 接口初始化第一位超级管理员
 # 该接口只能使用一次，一旦系统中存在超级管理员，此接口将永久拒绝请求
 setup_secret: ""
+
+# WebSocket 配置
+# 环境变量:
+#   APP_WEBSOCKET_MODE, APP_WEBSOCKET_CLUSTER_INSTANCE_ID
+#   APP_WEBSOCKET_CLUSTER_MSG_CHANNEL, APP_WEBSOCKET_CLUSTER_ONLINE_TTL
+#   APP_WEBSOCKET_CLUSTER_HEARTBEAT_INTERVAL
+websocket:
+  mode: standalone  # standalone 或 cluster
+  cluster:
+    instance_id: ""           # 留空自动生成 UUID
+    msg_channel: "ws:msg"     # Redis Pub/Sub 频道
+    online_ttl: 60            # 在线状态 TTL（秒）
+    heartbeat_interval: 20    # 心跳间隔（秒）