fix: update tests for group fallback

backend/internal/service/admin_service_group_test.go

@@ -458,6 +458,14 @@ func (s *groupRepoStubForInvalidRequestFallback) DeleteAccountGroupsByGroupID(_
 	panic("unexpected DeleteAccountGroupsByGroupID call")
 }
 
+func (s *groupRepoStubForInvalidRequestFallback) GetAccountIDsByGroupIDs(_ context.Context, _ []int64) ([]int64, error) {
+	panic("unexpected GetAccountIDsByGroupIDs call")
+}
+
+func (s *groupRepoStubForInvalidRequestFallback) BindAccountsToGroup(_ context.Context, _ int64, _ []int64) error {
+	panic("unexpected BindAccountsToGroup call")
+}
+
 func TestAdminService_CreateGroup_InvalidRequestFallbackRejectsUnsupportedPlatform(t *testing.T) {
 	fallbackID := int64(10)
 	repo := &groupRepoStubForInvalidRequestFallback{
@@ -764,4 +772,4 @@ func TestAdminService_UpdateGroup_InvalidRequestFallbackAllowsAntigravity(t *tes
 	require.NotNil(t, group)
 	require.NotNil(t, repo.updated)
 	require.Equal(t, fallbackID, *repo.updated.FallbackGroupIDOnInvalidRequest)
-	}
+}

backend/internal/service/antigravity_gateway_service.go

@@ -2046,6 +2046,9 @@ func (s *AntigravityGatewayService) handleUpstreamError(ctx context.Context, pre
 				fallbackMinutes = s.settingService.cfg.Gateway.AntigravityFallbackCooldownMinutes
 			}
 			defaultDur := time.Duration(fallbackMinutes) * time.Minute
+			if fallbackDur, ok := antigravityFallbackCooldownSeconds(); ok {
+				defaultDur = fallbackDur
+			}
 			ra := time.Now().Add(defaultDur)
 			if useScopeLimit {
 				log.Printf("%s status=429 rate_limited scope=%s reset_in=%v (fallback)", prefix, quotaScope, defaultDur)