fix: 插件路由注册 — 通过 fx 依赖注入确保插件构造并注册路由

- newEngine 接收 *ExamplePlugin 强制 fx 构造插件实例
- 直接调用 examplePlugin.SetupRoutes 注册路由
- 移除 plugin.All() 循环（避免双重注册）

internal/app/app.go

@@ -49,6 +49,7 @@ func newEngine(
 	auditHandler *auditinterfaces.Handler,
 	settingsHandler *settingsinterfaces.Handler,
 	notificationHandler *notificationinterfaces.Handler,
+	examplePlugin *exampleinterfaces.ExamplePlugin,
 ) *gin.Engine {
 	ginMode := "release"
 	if cfg.Server.Mode == "debug" || cfg.Server.Mode == "dev" {
@@ -77,9 +78,7 @@ func newEngine(
 	settingsinterfaces.SetupRoutes(r, settingsHandler, authMW)
 	notificationinterfaces.SetupRoutes(r, notificationHandler, authMW)
 
-	for _, p := range plugin.All() {
-		p.SetupRoutes(r, authMW)
-	}
+	examplePlugin.SetupRoutes(r, authMW)
 
 	return r
 }