feat(Sora): 完成Sora网关接入与媒体能力

新增 Sora 网关路由、账号调度与同步服务\n补充媒体代理与签名 URL、模型列表动态拉取\n完善计费配置、前端支持与相关测试

backend/internal/handler/handler.go

@@ -23,6 +23,7 @@ type AdminHandlers struct {
 	Subscription     *admin.SubscriptionHandler
 	Usage            *admin.UsageHandler
 	UserAttribute    *admin.UserAttributeHandler
+	Model            *admin.ModelHandler
 }
 
 // Handlers contains all HTTP handlers
@@ -36,6 +37,7 @@ type Handlers struct {
 	Admin         *AdminHandlers
 	Gateway       *GatewayHandler
 	OpenAIGateway *OpenAIGatewayHandler
+	SoraGateway   *SoraGatewayHandler
 	Setting       *SettingHandler
 }