优化：Redis 连接增强 — TCP keepalive 适配 + 截图处理器独立重连

- 新增 _build_keepalive_options() 适配 Linux/Windows TCP keepalive
- health_check_interval 30→15秒，更快发现断连
- 截图处理器新增 _reconnect_cloud_redis() 独立重连能力
- 截图监听捕获 ConnectionError 主动重连，不再退避到60秒

main.py

@@ -191,6 +191,7 @@ class EdgeInferenceService:
             try:
                 import redis
                 cfg = self._settings.cloud_redis
+                from core.config_sync import _build_keepalive_options
                 cloud_redis = redis.Redis(
                     host=cfg.host,
                     port=cfg.port,
@@ -201,7 +202,8 @@ class EdgeInferenceService:
                     socket_timeout=10,
                     retry_on_timeout=True,
                     socket_keepalive=True,
-                    health_check_interval=30,
+                    socket_keepalive_options=_build_keepalive_options(),
+                    health_check_interval=15,
                 )
                 cloud_redis.ping()
                 self._logger.info(f"截图处理器独立连接云端 Redis 成功: {cfg.host}:{cfg.port}/{cfg.db}")