feat: add USER_ID_MIDDLEWARE constant and update AuthMiddleware to use it

internal/middlewares/auth_middleware.go

@@ -4,6 +4,7 @@ import (
 	"net/http"
 	"strings"
 
+	"wm-backend/configs/constants"
 	"wm-backend/pkg/helper"
 	"wm-backend/response"
 
@@ -48,7 +49,7 @@ func AuthMiddleware() gin.HandlerFunc {
 		}
 
 		// 5. Set user_id in gin context for downstream handlers
-		c.Set("user_id", userID)
+		c.Set(constants.USER_ID_MIDDLEWARE, userID)
 		c.Next()
 	}
 }