feat(runner): implement cluster mode with Redis-based task dispatching and registry

Introduce a distributed task execution system for gRPC runners. This includes:
- A `TaskBus` for cluster-mode task dispatching via Redis Pub/Sub.
- A `RunnerRegistry` to track active runner instances in Redis.
- Support for both standalone and cluster modes via configuration.
- Refactored `RunnerHub` and `TaskManager` to use a `TaskDispatcher` interface, decoupling task submission from local execution.
- Added distributed locking to `HotRankWorker` to ensure only one instance performs periodic hot rank recalculations in a multi-instance deployment.
- Updated dependency injection (Wire) to support the new runner components and registry.

internal/config/config.go

@@ -33,6 +33,7 @@ type Config struct {
 	JPush             JPushConfig             `mapstructure:"jpush"`
 	SetupSecret       string                  `mapstructure:"setup_secret"`
 	WebSocket         WSConfig                `mapstructure:"websocket"`
+	Runner            RunnerConfig            `mapstructure:"runner"`
 }
 
 // Load 加载配置文件
@@ -180,6 +181,15 @@ func Load(configPath string) (*Config, error) {
 	viper.SetDefault("websocket.cluster.msg_channel", "ws:msg")
 	viper.SetDefault("websocket.cluster.online_ttl", 60)
 	viper.SetDefault("websocket.cluster.heartbeat_interval", 20)
+	// Runner 集群默认值（mode 和 instance_id 空则跟随 websocket）
+	viper.SetDefault("runner.mode", "")
+	viper.SetDefault("runner.cluster.instance_id", "")
+	viper.SetDefault("runner.cluster.task_channel", "runner:task")
+	viper.SetDefault("runner.cluster.result_channel", "runner:result")
+	viper.SetDefault("runner.cluster.registry_prefix", "runner:reg:")
+	viper.SetDefault("runner.cluster.cap_prefix", "runner:cap:")
+	viper.SetDefault("runner.cluster.registry_ttl", 90)
+	viper.SetDefault("runner.cluster.heartbeat_interval", 30)
 
 	if err := viper.ReadInConfig(); err != nil {
 		return nil, fmt.Errorf("failed to read config: %w", err)
@@ -190,6 +200,9 @@ func Load(configPath string) (*Config, error) {
 		return nil, fmt.Errorf("failed to unmarshal config: %w", err)
 	}
 
+	// Runner mode 和 instance_id 空则跟随 WebSocket 配置
+	cfg.Runner.ApplyWSDefaults(cfg.WebSocket)
+
 	// Convert seconds to duration
 	cfg.JWT.AccessTokenExpire = time.Duration(viper.GetInt("jwt.access_token_expire")) * time.Second
 	cfg.JWT.RefreshTokenExpire = time.Duration(viper.GetInt("jwt.refresh_token_expire")) * time.Second