添加Docker部署配置：backend Dockerfile、Caddyfile、docker-compose.yml，支持腾云云服务器部署域名skin.khhao.com，使用Caddy反向代理 + HTTPS

backend/internal/router/router.go

@@ -27,7 +27,7 @@ func Setup(h *Handlers) *gin.Engine {
 	r := gin.Default()
 
 	r.Use(cors.New(cors.Config{
-		AllowOrigins:     []string{"http://localhost:5173", "http://127.0.0.1:5173"},
+		AllowOrigins:     []string{"*"},
 		AllowMethods:     []string{"GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"},
 		AllowHeaders:     []string{"Origin", "Content-Type", "Authorization", "X-Api-Key", "X-Timestamp", "X-Nonce", "X-Sign"},
 		ExposeHeaders:    []string{"Content-Length"},