refactor: clean up project structure

- Remove old review reports (keep latest only)
- Move docs/ to deploy/docs-backup/
- Move performance-testing/ to deploy/
- Clean up test output files
- Organize root directory

backend/internal/handler/sora_client_handler_test.go

@@ -1058,6 +1058,9 @@ func (r *stubAPIKeyRepoForHandler) ResetRateLimitWindows(context.Context, int64)
 func (r *stubAPIKeyRepoForHandler) GetRateLimitData(context.Context, int64) (*service.APIKeyRateLimitData, error) {
 	return nil, nil
 }
+func (r *stubAPIKeyRepoForHandler) CountActiveByGroupID(context.Context, int64) (int64, error) {
+	return 0, nil
+}
 
 // newTestAPIKeyService 创建测试用的 APIKeyService
 func newTestAPIKeyService(repo *stubAPIKeyRepoForHandler) *service.APIKeyService {
@@ -2076,13 +2079,20 @@ func (r *stubAccountRepoForHandler) ListWithFilters(context.Context, pagination.
 	return nil, nil, nil
 }
 func (r *stubAccountRepoForHandler) ListByGroup(context.Context, int64) ([]service.Account, error) {
-	return nil, nil
+	return r.accounts, nil
 }
 func (r *stubAccountRepoForHandler) ListActive(context.Context) ([]service.Account, error) {
 	return nil, nil
 }
-func (r *stubAccountRepoForHandler) ListByPlatform(context.Context, string) ([]service.Account, error) {
-	return nil, nil
+func (r *stubAccountRepoForHandler) ListByPlatform(_ context.Context, platform string) ([]service.Account, error) {
+	// 返回匹配平台的账号
+	var result []service.Account
+	for _, acc := range r.accounts {
+		if acc.Platform == platform {
+			result = append(result, acc)
+		}
+	}
+	return result, nil
 }
 func (r *stubAccountRepoForHandler) UpdateLastUsed(context.Context, int64) error { return nil }
 func (r *stubAccountRepoForHandler) BatchUpdateLastUsed(context.Context, map[int64]time.Time) error {