feat(acceptance): 增加生产同构媒体压力验收模式

引入动态流量门禁、隔离验收身份与协议级 Gemini/Volces 模拟器，覆盖双站点 API、Worker、PostgreSQL、River、账务、回调和媒体物化链路。

新增 P24/P28/P32 容量阶梯、Worker 强杀恢复、真实小流量 canary、CAS 放量和失败保持 validation 的生产编排；Worker 执行槽、连接池、媒体并发和双站点副本数改为环境配置。

验证：Go 全量测试、真实 PostgreSQL 迁移集成测试、迁移安全检查、OpenAPI 生成、ShellCheck、Kustomize、gofmt 和 git diff --check。

apps/api/internal/store/tasks_runtime.go

@@ -294,7 +294,7 @@ func (s *Store) ClaimTaskExecution(ctx context.Context, taskID string, execution
 		if err := tx.QueryRow(ctx, `
 SELECT status = 'queued' AND next_run_at <= now(),
        status = 'running' AND (execution_lease_expires_at IS NULL OR execution_lease_expires_at <= now()),
-       run_mode = 'production',
+       run_mode IN ('production', 'acceptance', 'acceptance_canary'),
        gateway_user_id IS NOT NULL
 FROM gateway_tasks
 WHERE id = $1::uuid
@@ -431,7 +431,7 @@ SELECT status = 'queued'
            OR execution_lease_expires_at IS NULL
            OR execution_lease_expires_at <= now()
          ),
-       run_mode = 'production',
+       run_mode IN ('production', 'acceptance', 'acceptance_canary'),
        gateway_user_id IS NOT NULL
 FROM gateway_tasks
 WHERE id = $1::uuid
@@ -513,7 +513,7 @@ SET status = 'failed',
     error_code = NULLIF($2, ''),
     error_message = NULLIF($3, ''),
     billing_status = CASE
-      WHEN run_mode <> 'production' OR gateway_user_id IS NULL THEN 'not_required'
+      WHEN run_mode NOT IN ('production', 'acceptance', 'acceptance_canary') OR gateway_user_id IS NULL THEN 'not_required'
       ELSE 'released'
     END,
     billing_updated_at = now(),
@@ -910,7 +910,7 @@ SET status = 'cancelled',
     error_code = 'client_disconnected',
     error_message = NULLIF($3::text, ''),
     billing_status = CASE
-      WHEN run_mode <> 'production' OR gateway_user_id IS NULL THEN 'not_required'
+      WHEN run_mode NOT IN ('production', 'acceptance', 'acceptance_canary') OR gateway_user_id IS NULL THEN 'not_required'
       ELSE 'released'
     END,
     billing_updated_at = now(),
@@ -991,7 +991,7 @@ SET status = 'cancelled',
     error_code = 'task_cancelled',
     error_message = NULLIF($2, ''),
     billing_status = CASE
-      WHEN run_mode <> 'production' OR gateway_user_id IS NULL THEN 'not_required'
+      WHEN run_mode NOT IN ('production', 'acceptance', 'acceptance_canary') OR gateway_user_id IS NULL THEN 'not_required'
       WHEN reservation_amount > 0 THEN 'pending'
       ELSE 'released'
     END,
@@ -1027,7 +1027,7 @@ SELECT id, 'task.billing.release', 'release', reservation_amount, billing_curren
        pricing_snapshot, $2::jsonb, 'pending', now()
 FROM gateway_tasks
 WHERE id = $1::uuid
-  AND run_mode = 'production'
+  AND run_mode IN ('production', 'acceptance', 'acceptance_canary')
   AND gateway_user_id IS NOT NULL
   AND reservation_amount > 0
 ON CONFLICT (task_id, event_type) DO NOTHING`, taskID, string(payloadJSON))
@@ -1569,7 +1569,7 @@ SET status = 'succeeded',
     final_charge_amount = $9::numeric,
     billing_version = 'effective-pricing-v2',
     billing_status = CASE
-      WHEN run_mode = 'production' AND gateway_user_id IS NOT NULL THEN 'pending'
+      WHEN run_mode IN ('production', 'acceptance', 'acceptance_canary') AND gateway_user_id IS NOT NULL THEN 'pending'
       ELSE 'not_required'
     END,
     billing_currency = $10,
@@ -1624,7 +1624,7 @@ INSERT INTO settlement_outbox (
 SELECT id, 'task.billing.settle', 'settle', $2::numeric, $3, $4::jsonb, $5::jsonb, 'pending', now()
 FROM gateway_tasks
 WHERE id = $1::uuid
-  AND run_mode = 'production'
+  AND run_mode IN ('production', 'acceptance', 'acceptance_canary')
   AND gateway_user_id IS NOT NULL
 ON CONFLICT (task_id, event_type) DO NOTHING`,
 			input.TaskID, finalChargeAmount, currency, string(pricingSnapshotJSON), string(payloadJSON))
@@ -1725,7 +1725,7 @@ SELECT id, 'task.billing.review', 'release', reservation_amount, billing_currenc
        pricing_snapshot, $2::jsonb, 'manual_review', now(), $3
 FROM gateway_tasks
 WHERE id = $1::uuid
-  AND run_mode = 'production'
+  AND run_mode IN ('production', 'acceptance', 'acceptance_canary')
   AND gateway_user_id IS NOT NULL
 ON CONFLICT (task_id, event_type) DO NOTHING`, input.TaskID, string(payloadJSON), input.Code)
 		return err
@@ -1902,7 +1902,7 @@ func (s *Store) FinishTaskFailure(ctx context.Context, input FinishTaskFailureIn
 	    response_duration_ms = $8,
 	    result = $9::jsonb,
 	    billing_status = CASE
-	      WHEN run_mode <> 'production' OR gateway_user_id IS NULL THEN 'not_required'
+	      WHEN run_mode NOT IN ('production', 'acceptance', 'acceptance_canary') OR gateway_user_id IS NULL THEN 'not_required'
 	      WHEN reservation_amount > 0 THEN 'pending'
 	      ELSE 'released'
 	    END,
@@ -1944,7 +1944,7 @@ SELECT id, 'task.billing.release', 'release', reservation_amount, billing_curren
        pricing_snapshot, $2::jsonb, 'pending', now()
 FROM gateway_tasks
 WHERE id = $1::uuid
-  AND run_mode = 'production'
+  AND run_mode IN ('production', 'acceptance', 'acceptance_canary')
   AND gateway_user_id IS NOT NULL
   AND reservation_amount > 0
 ON CONFLICT (task_id, event_type) DO NOTHING`, input.TaskID, string(payloadJSON))