Integrate WeChat Official Account support and update configuration

- Added WeChat Official Account configuration options to .env.example and config.go for OAuth2 integration.
- Updated main.go to initialize WeChat OAuth handler and register routes for handling OAuth requests.
- Enhanced documentation to include references for WeChat Official Account functionality.
- Updated route registration to accommodate the new OAuth handler for improved API structure.

internal/routes/routes.go

@@ -8,6 +8,7 @@ import (
 
 	authhandler "wx_service/internal/common/auth/handler"
 	qiniuhandler "wx_service/internal/common/qiniu/handler"
+	oahandler "wx_service/internal/common/wechat_official/handler"
 	"wx_service/internal/middleware"
 	rmhandler "wx_service/internal/remove_watermark/handler"
 	smokehandler "wx_service/internal/smoke/handler"
@@ -20,6 +21,7 @@ func Register(
 	videoHandler *rmhandler.VideoHandler,
 	smokeHandler *smokehandler.SmokeHandler,
 	uploadHandler *qiniuhandler.UploadHandler,
+	oaOAuthHandler *oahandler.OAuthHandler,
 ) {
 	// 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）
@@ -29,6 +31,9 @@ func Register(
 		// 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)
 
+		// 公众号网页授权：不需要登录（code 本身来自微信授权回调）
+		registerWeChatOfficialRoutes(api, oaOAuthHandler)
+
 		// 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))

internal/routes/wechat_official_routes.go

@@ -0,0 +1,15 @@
+package routes
+
+import (
+	"github.com/gin-gonic/gin"
+
+	oahandler "wx_service/internal/common/wechat_official/handler"
+)
+
+func registerWeChatOfficialRoutes(api *gin.RouterGroup, oauthHandler *oahandler.OAuthHandler) {
+	// 微信公众号（网页授权 OAuth2）
+	oa := api.Group("/wechat/official")
+	{
+		oa.POST("/oauth/code2user", oauthHandler.CodeToUser)
+	}
+}