fix: 修复构建配置和运行时错误处理

backend/internal/middleware/redis/cache.go

@@ -2,21 +2,34 @@ package redis
 
 import (
 	"context"
+	"errors"
 	"time"
 )
 
 func (c *Client) GetBytes(ctx context.Context, key string) ([]byte, error) {
+	if c == nil || c.rdb == nil {
+		return nil, errors.New("redis client not initialized")
+	}
 	return c.rdb.Get(ctx, key).Bytes()
 }
 
 func (c *Client) SetBytes(ctx context.Context, key string, value []byte, ttl time.Duration) error {
+	if c == nil || c.rdb == nil {
+		return errors.New("redis client not initialized")
+	}
 	return c.rdb.Set(ctx, key, value, ttl).Err()
 }
 
 func (c *Client) Del(ctx context.Context, key string) error {
+	if c == nil || c.rdb == nil {
+		return errors.New("redis client not initialized")
+	}
 	return c.rdb.Del(ctx, key).Err()
 }
 
 func (c *Client) MGet(cacheCtx context.Context, cacheKeys ...string) ([]interface{}, error) {
+	if c == nil || c.rdb == nil {
+		return nil, errors.New("redis client not initialized")
+	}
 	return c.rdb.MGet(cacheCtx, cacheKeys...).Result()
 }