feat: 初始化后端服务骨架，包含配置加载、数据库连接、Redis集成及消息队列任务处理。

internal/config/config.go

@@ -58,6 +58,10 @@ type Config struct {
 	MaxImageSize      int64
 	AllowedImageTypes string
 	MaxImagesPerTx    int
+
+	// Task Queue configuration
+	MQWorkerCount  int
+	MQPollInterval time.Duration
 }
 
 // Load loads configuration from environment variables
@@ -113,6 +117,10 @@ func Load() *Config {
 		MaxImageSize:      getEnvInt64("MAX_IMAGE_SIZE", 10*1024*1024), // 10MB
 		AllowedImageTypes: getEnv("ALLOWED_IMAGE_TYPES", "image/jpeg,image/png,image/heic"),
 		MaxImagesPerTx:    getEnvInt("MAX_IMAGES_PER_TX", 9),
+
+		// Task Queue
+		MQWorkerCount:  getEnvInt("MQ_WORKER_COUNT", 2),
+		MQPollInterval: getEnvDuration("MQ_POLL_INTERVAL", 5*time.Second),
 	}
 
 	// Ensure data directory exists