fix(v2): jiu 反馈波——端型透传(wap/page)+ alipay qr(当面付移植)+ 单号增熵/挡板限流

1. CreateOrderInput/RetryOrder 加 Metadata 通道,handler 白名单过滤(is_mobile/render)
   后原样传给 provider.CreateRequest;alipay adapter 据 is_mobile 选 wap/page。
2. alipay adapter 移植 v1 当面付(TradePreCreate):Metadata["render"]=="qr" → 二维码
   render_type,payload={qr_content,display_amount,currency},默认 2 小时窗口。
3. NewOutTradeNo 随机部分 8→16 hex 防生日碰撞(仍 <=64 字符,合规 DB 列/支付宝上限);
   v2 改状态端点(下单/重试/取消)加 per-IP 内存令牌桶限流,默认开 30/min,
   config.rate_limit.disabled 可关;callback/GET 查询不限。

顺带修:internal/reconcile/sync_test.go 的 gateway.New 调用漏传 refunds store,
预先存在的编译期回归(与本次改动无关,但挡住 go test ./... 全绿,一并修掉)。

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013nMthbVEmQquxBRKb9Fj8u

internal/reconcile/sync_test.go

@@ -30,11 +30,12 @@ func (nopEnq) Enqueue(_, _, _, _ string, _ map[string]any) error { return nil }
 func TestSyncPendingTaskSettlesViaQuery(t *testing.T) {
 	db := model.OpenTestDB(t)
 	orders := store.NewOrderStore(db)
+	refunds := store.NewRefundStore(db)
 	preg := provider.NewRegistry()
 	fp := fake.New()
 	preg.Register(fp)
 	areg := accounts.New([]config.AccountConfig{{AccountID: "fake-a1", Channel: "fake", Region: "global", Enabled: true}})
-	gw := gateway.New(orders, preg, accounts.NewRouter(areg, nil, nil), stubResolver{}, nopEnq{}, "global")
+	gw := gateway.New(orders, refunds, preg, accounts.NewRouter(areg, nil, nil), stubResolver{}, nopEnq{}, "global")
 
 	res, _ := gw.CreateOrder(context.Background(), gateway.CreateOrderInput{SKU: "pro_year", Method: "fake", BizSystem: "pangolin", BizRef: "u-1"})
 	atts, _ := orders.ListAttemptsByStatus(model.AttemptPending, 10)