feat(cost-center): 卡券商品创建即生成渠道规则，补齐成本项预设

- 新建 tpv: 商品时自动写 third_party_voucher 规则，避免新卡券 SKU 停在待分类
- 成本项预设新增「第三方卡券采购成本」

apps/backend/src/services/cost-center/product-catalog-service.ts

@@ -16,6 +16,7 @@ import { nowIso } from '../../utils/time.js'
 import { normalizeMatchText, normalizeSkuSeriesEquivalence } from '../product-match/normalize.js'
 import { resolveSkuNameQuantity } from '../product-match/pricing.js'
 import { setAdminAffiliateProductPrice } from './affiliate-product-service.js'
+import { ensureVoucherRuleForSku } from '../fulfillment/channel-assign-service.js'
 import { syncAdminWorkProductRulePrice } from '../worker-platform/admin-worker-catalog-service.js'
 import {
   AFFILIATE_TASK_AGG_JOIN,
@@ -345,6 +346,10 @@ export async function createAdminProduct(payload: JsonObject, _session: AdminSes
       errorCode: 'cost_product_sku_exists',
     })
   }
+  // 卡券没有载体证据，创建商品时顺手把渠道规则补上，避免新 SKU 停在待分类。
+  if (canonicalSku.startsWith('tpv:')) {
+    await ensureVoucherRuleForSku(canonicalSku.slice(4))
+  }
   return { product: mapProduct(inserted) }
 }
 

apps/backend/src/services/fulfillment/channel-assign-service.ts

@@ -553,6 +553,25 @@ export const CHANNEL_RULE_KEY_TYPES = MATCH_KEY_TYPES
 export const CHANNEL_RULE_SOURCES = RULE_SOURCES
 export const CHANNEL_VALUES = FULFILLMENT_CHANNELS
 
+/** 为单个卡券 SKU 建规则（商品创建时调用，幂等）。 */
+export async function ensureVoucherRuleForSku(skuCode: string): Promise<boolean> {
+  const key = String(skuCode || '').trim()
+  if (!key) return false
+  const result = await query<{ id: number }>(
+    `
+      INSERT INTO sku_channel_rules (
+        provider, shop_id, match_key_type, match_key, channel, priority,
+        source, enabled, note, created_at, updated_at
+      )
+      VALUES ('', '', 'sku_code', $1, 'third_party_voucher', 70, 'voucher', TRUE, '卡券商品自动生成', NOW(), NOW())
+      ON CONFLICT (provider, shop_id, match_key_type, match_key, channel) DO NOTHING
+      RETURNING id
+    `,
+    [key],
+  )
+  return (result.rowCount || 0) > 0
+}
+
 /**
  * 为卡券商品（tpv: 前缀）批量补渠道规则。
  *

apps/frontend/src/pages/admin/cost-center/shared.ts

@@ -171,6 +171,14 @@ export const COST_ITEM_PRESETS: CostItemPreset[] = [
     pricingMode: 'per_item',
     unitName: '件',
   },
+  {
+    key: 'third_party_voucher_cost',
+    label: '第三方卡券采购成本',
+    name: '第三方卡券采购成本',
+    costModel: 'third_party_voucher_cost',
+    pricingMode: 'per_item',
+    unitName: '件',
+  },
   {
     key: 'work_order_reward',
     label: '接单平台打手报酬',