feat(acceptance): 建立同构验收与弹性容量体系

实现本地三节点 K3s 同构环境、脱敏生产快照、Gemini 图片和多参考图视频协议模拟、统一验收报告及故障注入。\n\n新增 Worker 容量控制器、资源与连接预算、任务恢复保护，并将生产验收拆分为 validation 执行和人工 CAS 放量。\n\n验证包括 Go 全量测试、PostgreSQL HTTP 集成测试、go vet、OpenAPI、ShellCheck、前端检查、迁移及发布脚本测试。

apps/api/internal/httpapi/handlers.go

@@ -178,9 +178,45 @@ func (s *Server) logPostgresUnavailable(message string) {
 		"postgres_pool_idle_connections", statistics.IdleConns(),
 		"postgres_pool_empty_acquire_count", statistics.EmptyAcquireCount(),
 		"postgres_pool_canceled_acquire_count", statistics.CanceledAcquireCount(),
+		"postgres_critical_pool", s.criticalPostgresPoolLogFields(),
+		"postgres_river_pool", s.riverPostgresPoolLogFields(),
 	)
 }
 
+func (s *Server) criticalPostgresPoolLogFields() map[string]any {
+	if s.coordinationStore == nil || s.coordinationStore == s.store ||
+		s.coordinationStore.Pool() == nil {
+		return map[string]any{"separate": false}
+	}
+	statistics := s.coordinationStore.Pool().Stat()
+	return map[string]any{
+		"separate":               true,
+		"max_connections":        statistics.MaxConns(),
+		"total_connections":      statistics.TotalConns(),
+		"acquired_connections":   statistics.AcquiredConns(),
+		"idle_connections":       statistics.IdleConns(),
+		"empty_acquire_count":    statistics.EmptyAcquireCount(),
+		"canceled_acquire_count": statistics.CanceledAcquireCount(),
+	}
+}
+
+func (s *Server) riverPostgresPoolLogFields() map[string]any {
+	if s.riverStore == nil || s.riverStore == s.store ||
+		s.riverStore.Pool() == nil {
+		return map[string]any{"separate": false}
+	}
+	statistics := s.riverStore.Pool().Stat()
+	return map[string]any{
+		"separate":               true,
+		"max_connections":        statistics.MaxConns(),
+		"total_connections":      statistics.TotalConns(),
+		"acquired_connections":   statistics.AcquiredConns(),
+		"idle_connections":       statistics.IdleConns(),
+		"empty_acquire_count":    statistics.EmptyAcquireCount(),
+		"canceled_acquire_count": statistics.CanceledAcquireCount(),
+	}
+}
+
 func (s *Server) localIdentityEnabled() bool {
 	mode := strings.ToLower(strings.TrimSpace(s.cfg.IdentityMode))
 	return mode == "" || mode == "standalone" || mode == "hybrid"
@@ -1183,6 +1219,11 @@ func (s *Server) createTask(kind string, compatible bool) http.Handler {
 		}
 		created, err := s.store.CreateTaskIdempotent(r.Context(), createInput, user)
 		if err != nil {
+			if errors.Is(err, store.ErrRateLimited) {
+				applyRunErrorHeaders(w, err)
+				writeTaskError(statusFromRunError(err), runErrorMessage(err), runErrorDetails(err), runErrorCode(err))
+				return
+			}
 			if errors.Is(err, store.ErrIdempotencyKeyReused) {
 				writeTaskError(http.StatusConflict, "Idempotency-Key was reused for a different request", nil, "idempotency_key_reused")
 				return
@@ -1200,8 +1241,9 @@ func (s *Server) createTask(kind string, compatible bool) http.Handler {
 			if s.billingMetrics != nil {
 				s.billingMetrics.ObserveBillingEvent("idempotent_replay")
 			}
-			if targetProtocol == "" {
+			if targetProtocol == "" || gatewayAPIV1Request(r) {
 				w.Header().Set("Idempotent-Replayed", "true")
+				w.Header().Set("X-Gateway-Task-Id", task.ID)
 			}
 			if responsePlan.streamMode {
 				writeTaskError(http.StatusConflict, "streaming idempotent replay is not supported", nil, "idempotency_stream_replay_unsupported")
@@ -1411,7 +1453,7 @@ func writeCompatibleTaskResponse(runCtx context.Context, w http.ResponseWriter,
 }
 
 func writeProtocolCompatibleTaskResponse(runCtx context.Context, w http.ResponseWriter, r *http.Request, executor taskExecutor, kind string, model string, targetProtocol string, task store.GatewayTask, user *auth.User, streamMode bool, includeUsage bool) {
-	if targetProtocol == "" {
+	if targetProtocol == "" || gatewayAPIV1Request(r) {
 		w.Header().Set("X-Gateway-Task-Id", task.ID)
 	}
 	if streamMode {
@@ -1515,6 +1557,10 @@ func writeProtocolCompatibleTaskResponse(runCtx context.Context, w http.Response
 	writeJSON(w, http.StatusOK, easyAISynchronousTaskResponse(result.Task, result.Output))
 }
 
+func gatewayAPIV1Request(r *http.Request) bool {
+	return r != nil && strings.HasPrefix(r.URL.Path, "/api/v1/")
+}
+
 func streamIncludeUsage(body map[string]any) bool {
 	streamOptions, _ := body["stream_options"].(map[string]any)
 	includeUsage, _ := streamOptions["include_usage"].(bool)