refactor(logging): replace gin-specific context handling with generic context-based request metadata utilities

- Introduced reusable utilities in `requestmeta` to manage endpoint and response status in request contexts.
- Refactored plugins and handlers to use context-based metadata, removing direct dependency on `gin`.
- Updated tests to validate new context utilities and replaced `gin`-based context handling.

Fixed: #3166

internal/redisqueue/plugin.go

@@ -3,11 +3,9 @@ package redisqueue
 import (
 	"context"
 	"encoding/json"
-	"net/http"
 	"strings"
 	"time"
 
-	"github.com/gin-gonic/gin"
 	internallogging "github.com/router-for-me/CLIProxyAPI/v6/internal/logging"
 	internalusage "github.com/router-for-me/CLIProxyAPI/v6/internal/usage"
 	coreusage "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/usage"
@@ -46,11 +44,6 @@ func (p *usageQueuePlugin) HandleUsage(ctx context.Context, record coreusage.Rec
 	}
 	apiKey := strings.TrimSpace(record.APIKey)
 	requestID := strings.TrimSpace(internallogging.GetRequestID(ctx))
-	if requestID == "" {
-		if ginCtx, ok := ctx.Value("gin").(*gin.Context); ok && ginCtx != nil {
-			requestID = strings.TrimSpace(internallogging.GetGinRequestID(ginCtx))
-		}
-	}
 
 	tokens := internalusage.TokenStats{
 		InputTokens:     record.Detail.InputTokens,
@@ -106,40 +99,15 @@ type queuedUsageDetail struct {
 }
 
 func resolveSuccess(ctx context.Context) bool {
-	if ctx == nil {
-		return true
-	}
-	ginCtx, ok := ctx.Value("gin").(*gin.Context)
-	if !ok || ginCtx == nil {
-		return true
-	}
-	status := ginCtx.Writer.Status()
+	status := internallogging.GetResponseStatus(ctx)
 	if status == 0 {
 		return true
 	}
-	return status < http.StatusBadRequest
+	return status < httpStatusBadRequest
 }
 
 func resolveEndpoint(ctx context.Context) string {
-	if ctx == nil {
-		return ""
-	}
-	ginCtx, ok := ctx.Value("gin").(*gin.Context)
-	if !ok || ginCtx == nil || ginCtx.Request == nil {
-		return ""
-	}
-
-	path := strings.TrimSpace(ginCtx.FullPath())
-	if path == "" && ginCtx.Request.URL != nil {
-		path = strings.TrimSpace(ginCtx.Request.URL.Path)
-	}
-	if path == "" {
-		return ""
-	}
-
-	method := strings.TrimSpace(ginCtx.Request.Method)
-	if method == "" {
-		return path
-	}
-	return method + " " + path
+	return strings.TrimSpace(internallogging.GetEndpoint(ctx))
 }
+
+const httpStatusBadRequest = 400