fix(finance): 卡券商品补内部 SKU 规则，待分类自动分流

- 自动创建 tpv: 商品时补渠道能力和 internal_sku 规则
- 迁移 116 为已存在的卡券商品回填内部 SKU 规则
- 同内部中文 SKU 的待分类订单自动进入第三方卡券

apps/backend/src/db/migrations/116_voucher_internal_sku_backfill.sql

@@ -0,0 +1,23 @@
+-- 116_voucher_internal_sku_backfill.sql
+--
+-- 为已存在的三方卡券商品补齐渠道能力和内部中文 SKU 规则：
+-- 卡券商品可能是自动创建后才补的迁移，旧商品没有 capability；
+-- 补齐后同内部 SKU 的不同平台码会由 channel_assign 自动分流到卡券渠道。
+
+INSERT INTO product_channel_capabilities (product_id, channel, priority, is_fallback, enabled, source)
+SELECT p.id, 'third_party_voucher', 10, FALSE, TRUE, 'backfill'
+FROM product_catalog p
+WHERE p.status = 'active' AND p.canonical_sku LIKE 'tpv:%'
+ON CONFLICT (product_id, channel) DO NOTHING;
+
+INSERT INTO sku_channel_rules (
+  provider, shop_id, match_key_type, match_key, channel, priority,
+  source, enabled, note, created_at, updated_at
+)
+SELECT '', '', 'internal_sku', btrim(p.canonical_name), 'third_party_voucher', 10,
+       'voucher', TRUE, '卡券商品内部SKU回填', NOW(), NOW()
+FROM product_catalog p
+WHERE p.status = 'active'
+  AND p.canonical_sku LIKE 'tpv:%'
+  AND btrim(p.canonical_name) <> ''
+ON CONFLICT (provider, shop_id, match_key_type, match_key, channel) DO NOTHING;

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

@@ -182,6 +182,29 @@ async function ensureVoucherProductForItem(item: ItemRow): Promise<number | null
     [item.id, productId],
   )
 
+  await query(
+    `
+      INSERT INTO product_channel_capabilities (product_id, channel, priority, is_fallback, enabled, source)
+      VALUES ($1, 'third_party_voucher', 10, FALSE, TRUE, 'auto')
+      ON CONFLICT (product_id, channel) DO NOTHING
+    `,
+    [productId],
+  )
+
+  // 同一内部中文 SKU 跨平台码统一分流到卡券渠道。
+  await query(
+    `
+      INSERT INTO sku_channel_rules (
+        provider, shop_id, match_key_type, match_key, channel, priority,
+        source, enabled, note, created_at, updated_at
+      )
+      VALUES ('', '', 'internal_sku', $1, 'third_party_voucher', 10, 'voucher', TRUE,
+              '卡券商品自动建商品后生成', NOW(), NOW())
+      ON CONFLICT (provider, shop_id, match_key_type, match_key, channel) DO NOTHING
+    `,
+    [internalSku],
+  )
+
   const skuCode = String(item.sku_code || '').trim()
   if (skuCode) {
     await query(