fix: 补充测试桩缺失的接口方法

backend/internal/handler/admin/admin_service_stub_test.go

@@ -200,6 +200,10 @@ func (s *stubAdminService) ClearAccountError(ctx context.Context, id int64) (*se
 	return &account, nil
 }
 
+func (s *stubAdminService) SetAccountError(ctx context.Context, id int64, errorMsg string) error {
+	return nil
+}
+
 func (s *stubAdminService) SetAccountSchedulable(ctx context.Context, id int64, schedulable bool) (*service.Account, error) {
 	account := service.Account{ID: id, Name: "account", Status: service.StatusActive, Schedulable: schedulable}
 	return &account, nil

backend/internal/service/antigravity_rate_limit_test.go

@@ -38,6 +38,10 @@ func (s *stubAntigravityUpstream) Do(req *http.Request, proxyURL string, account
 	}, nil
 }
 
+func (s *stubAntigravityUpstream) DoWithTLS(req *http.Request, proxyURL string, accountID int64, accountConcurrency int, enableTLSFingerprint bool) (*http.Response, error) {
+	return s.Do(req, proxyURL, accountID, accountConcurrency)
+}
+
 type scopeLimitCall struct {
 	accountID int64
 	scope     AntigravityQuotaScope