merge: 合并 main 分支到 test，解决 config 和 modelWhitelist 冲突

- config.go: 保留 Sora 配置，合入 SubscriptionCache 配置
- useModelWhitelist.ts: 同时保留 soraModels 和 antigravityModels

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/internal/service/admin_service.go

@@ -56,6 +56,7 @@ type AdminService interface {
 	GetAllProxies(ctx context.Context) ([]Proxy, error)
 	GetAllProxiesWithAccountCount(ctx context.Context) ([]ProxyWithAccountCount, error)
 	GetProxy(ctx context.Context, id int64) (*Proxy, error)
+	GetProxiesByIDs(ctx context.Context, ids []int64) ([]Proxy, error)
 	CreateProxy(ctx context.Context, input *CreateProxyInput) (*Proxy, error)
 	UpdateProxy(ctx context.Context, id int64, input *UpdateProxyInput) (*Proxy, error)
 	DeleteProxy(ctx context.Context, id int64) error
@@ -179,6 +180,8 @@ type CreateAccountInput struct {
 	GroupIDs           []int64
 	ExpiresAt          *int64
 	AutoPauseOnExpired *bool
+	// SkipDefaultGroupBind prevents auto-binding to platform default group when GroupIDs is empty.
+	SkipDefaultGroupBind bool
 	// SkipMixedChannelCheck skips the mixed channel risk check when binding groups.
 	// This should only be set when the caller has explicitly confirmed the risk.
 	SkipMixedChannelCheck bool
@@ -1076,7 +1079,7 @@ func (s *adminServiceImpl) CreateAccount(ctx context.Context, input *CreateAccou
 	// 绑定分组
 	groupIDs := input.GroupIDs
 	// 如果没有指定分组,自动绑定对应平台的默认分组
-	if len(groupIDs) == 0 {
+	if len(groupIDs) == 0 && !input.SkipDefaultGroupBind {
 		defaultGroupName := input.Platform + "-default"
 		groups, err := s.groupRepo.ListActiveByPlatform(ctx, input.Platform)
 		if err == nil {
@@ -1444,6 +1447,10 @@ func (s *adminServiceImpl) GetProxy(ctx context.Context, id int64) (*Proxy, erro
 	return s.proxyRepo.GetByID(ctx, id)
 }
 
+func (s *adminServiceImpl) GetProxiesByIDs(ctx context.Context, ids []int64) ([]Proxy, error) {
+	return s.proxyRepo.ListByIDs(ctx, ids)
+}
+
 func (s *adminServiceImpl) CreateProxy(ctx context.Context, input *CreateProxyInput) (*Proxy, error) {
 	proxy := &Proxy{
 		Name:     input.Name,