refactor: improve system stability, performance, and code structure

This commit introduces several architectural improvements and optimizations across the codebase:

- **Performance & Reliability**:
  - Implemented Redis pipelining in `ConversationCache.CacheMessage` to reduce network round-trips.
  - Added a circuit breaker to the JPush client to prevent cascading failures.
  - Introduced batch deletion and batch member addition capabilities in repositories.
  - Added message idempotency support using `client_msg_id` and a Redis-based cache.
  - Optimized WebSocket handling with connection limits (total and per-user) and improved error logging.

- **Code Refactoring**:
  - Refactored `Router` to use a `RouterDeps` struct, simplifying the constructor and improving maintainability.
  - Unified model ID generation logic using new `id_helper.go` (supporting UUID and Snowflake).
  - Standardized JSON serialization/deserialization in models using `json_helper.go`.
  - Refactored DTO conversion logic, specifically for `UserResponse` (using functional options) and `Report` responses.
  - Removed redundant/deprecated DTOs like `PostDetailResponse` and `TradeItemDetailResponse`.

- **Cache Improvements**:
  - Enhanced `LayeredCache` with `SetRaw` to avoid double-encoding when promoting values from Redis to local cache.
  - Added `DeleteBatch` support to the cache interface.

- **Other Changes**:
  - Cleaned up `config.go` by removing redundant default values and explicit environment variable overrides.
  - Improved WebSocket registration flow to handle connection limits gracefully.

internal/cache/conversation_cache.go

@@ -6,6 +6,8 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/redis/go-redis/v9"
+
 	"with_you/internal/model"
 
 	"go.uber.org/zap"
@@ -618,11 +620,11 @@ func (c *ConversationCache) GetMessagesBeforeSeq(ctx context.Context, convID str
 	return messages, nil
 }
 
-// CacheMessage 缓存单条消息（立即写入缓存）
-// 写入 Hash、Sorted Set、更新计数
+// CacheMessage 缓存单条消息（使用 Redis Pipeline 减少网络往返）
 func (c *ConversationCache) CacheMessage(ctx context.Context, convID string, msg *model.Message) error {
 	hashKey := MessageHashKey(convID)
 	indexKey := MessageIndexKey(convID)
+	countKey := MessageCountKey(convID)
 
 	msgData := MessageCacheDataFromModel(msg)
 	data, err := json.Marshal(msgData)
@@ -630,23 +632,34 @@ func (c *ConversationCache) CacheMessage(ctx context.Context, convID string, msg
 		return fmt.Errorf("failed to marshal message: %w", err)
 	}
 
-	// HSET 消息详情
-	if err := c.cache.HSet(ctx, hashKey, fmt.Sprintf("%d", msg.Seq), string(data)); err != nil {
+	hashKey = ResolveKey(hashKey)
+	indexKey = ResolveKey(indexKey)
+	countKey = ResolveKey(countKey)
+
+	redisCache, ok := c.cache.(*RedisCache)
+	if ok {
+		rdb := redisCache.GetRedisClient().GetClient()
+		pipe := rdb.Pipeline()
+		pipe.HSet(ctx, hashKey, fmt.Sprintf("%d", msg.Seq), string(data))
+		pipe.ZAdd(ctx, indexKey, redis.Z{Score: float64(msg.Seq), Member: fmt.Sprintf("%d", msg.Seq)})
+		pipe.Expire(ctx, hashKey, c.settings.MessageDetailTTL)
+		pipe.Expire(ctx, indexKey, c.settings.MessageIndexTTL)
+		pipe.Incr(ctx, countKey)
+		if _, err := pipe.Exec(ctx); err != nil {
+			return fmt.Errorf("failed to pipeline cache message: %w", err)
+		}
+		return nil
+	}
+
+	if err := c.cache.HSet(ctx, MessageHashKey(convID), fmt.Sprintf("%d", msg.Seq), string(data)); err != nil {
 		return fmt.Errorf("failed to set hash: %w", err)
 	}
-
-	// ZADD 消息索引
-	if err := c.cache.ZAdd(ctx, indexKey, float64(msg.Seq), fmt.Sprintf("%d", msg.Seq)); err != nil {
+	if err := c.cache.ZAdd(ctx, MessageIndexKey(convID), float64(msg.Seq), fmt.Sprintf("%d", msg.Seq)); err != nil {
 		return fmt.Errorf("failed to add to sorted set: %w", err)
 	}
-
-	// 设置 TTL
-	c.cache.Expire(ctx, hashKey, c.settings.MessageDetailTTL)
-	c.cache.Expire(ctx, indexKey, c.settings.MessageIndexTTL)
-
-	// INCR 消息计数
+	c.cache.Expire(ctx, MessageHashKey(convID), c.settings.MessageDetailTTL)
+	c.cache.Expire(ctx, MessageIndexKey(convID), c.settings.MessageIndexTTL)
 	c.cache.Incr(ctx, MessageCountKey(convID))
-
 	return nil
 }