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/pkg/jpush/client.go

@@ -13,6 +13,8 @@ import (
 	"strconv"
 	"time"
 
+	"with_you/internal/pkg/circuitbreaker"
+
 	"go.uber.org/zap"
 )
 
@@ -29,6 +31,7 @@ type Client struct {
 	httpClient    *http.Client
 	logger        *zap.Logger
 	lastRateLimit *RateLimitInfo
+	breaker       *circuitbreaker.Breaker
 }
 
 func NewClient(appKey, masterSecret string, production bool, logger *zap.Logger) *Client {
@@ -48,6 +51,12 @@ func NewClient(appKey, masterSecret string, production bool, logger *zap.Logger)
 		production:   production,
 		httpClient:   &http.Client{Timeout: 30 * time.Second, Transport: transport},
 		logger:       logger,
+		breaker: circuitbreaker.New(circuitbreaker.Config{
+			FailureThreshold: 5,
+			SuccessThreshold: 3,
+			Timeout:          30 * time.Second,
+			Name:             "jpush",
+		}),
 	}
 }
 
@@ -259,7 +268,15 @@ func (c *Client) PushByRegistrationIDs(registrationIDs []string, notification *N
 		},
 	}
 
-	result, _, err := c.Push(payload)
+	var result *PushResponse
+	err := c.breaker.Execute(func() error {
+		resp, _, pushErr := c.Push(payload)
+		if pushErr != nil {
+			return pushErr
+		}
+		result = resp
+		return nil
+	})
 	if err != nil {
 		c.logger.Error("jpush push by registration_ids failed",
 			zap.Int("count", len(registrationIDs)),