feat(admin): 存储管理 - 新增资源只读查询、统计与预览

Adapted from ddcat-ai/open-ai-canvas#339

Original commit: fcdbe2aa833f31f683f709b7f409a0534ed78e20

Refs #339

Co-authored-by: 宇熙 <101980758+yuxiwl@users.noreply.github.com>

backend/cmd/server/main.go

@@ -84,6 +84,7 @@ func main() {
 	handler.RegisterResponseInterceptionRoutes(api, svc)
 	handler.RegisterAdminRoutes(api, svc)
 	handler.RegisterAdminAnalyticsRoutes(api, svc)
+	handler.RegisterAdminStorageRoutes(api, svc)
 	handler.RegisterAnnouncementRoutes(api, svc)
 	handler.RegisterFinanceRoutes(api, svc)
 	handler.RegisterLibTVRoutes(api, svc)