Enhance API and error handling for video services

- Updated .gitignore to exclude cache files.
- Refactored main.go to streamline route registration and improve code organization.
- Added detailed comments in auth_handler.go, video_handler.go, and service files for better clarity on request handling and service logic.
- Improved error messages in video_handler.go to provide clearer feedback to users in Chinese.
- Introduced context handling in service methods to manage request timeouts effectively.

internal/routes/routes.go

@@ -0,0 +1,35 @@
+package routes
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"gorm.io/gorm"
+
+	"wx_service/internal/handler"
+	"wx_service/internal/middleware"
+)
+
+func Register(router *gin.Engine, db *gorm.DB, authHandler *handler.AuthHandler, videoHandler *handler.VideoHandler) {
+	// Register 用来集中注册所有 HTTP 路由，便于工程结构更清晰：
+	// - main 只负责初始化（配置/DB/依赖注入）
+	// - routes 只负责把 URL 映射到 handler
+	api := router.Group("/api/v1")
+	{
+		// 登录接口：用微信 code 换取/创建用户并返回 session_key（作为后续 Bearer Token）
+		api.POST("/auth/login", authHandler.LoginWithWeChat)
+
+		// 需要登录的接口组：统一挂载鉴权中间件
+		protected := api.Group("")
+		protected.Use(middleware.AuthMiddleware(db))
+		{
+			protected.POST("/video/remove_watermark", videoHandler.RemoveWatermark)
+			protected.POST("/video/remove_watermark/unlock", videoHandler.UnlockQuota)
+		}
+	}
+
+	// 健康检查：用于容器/负载均衡探活
+	router.GET("/healthz", func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{"status": "ok"})
+	})
+}