feat(backend): 入库/出库列表 keyword 支持酒名模糊反查

- keyword 在单号/往来单位基础上，新增按酒名反查含该酒明细的单据
- 酒名匹配复用拼音基建：name(优先 product 回退快照) + name_pinyin + name_initials
- 子查询带 shop_id，多租户隔离不破
- 补 stock_in/stock_out List 按酒名+拼音命中的测试用例

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/internal/handler/stock_out.go

@@ -45,9 +45,17 @@ func (h *StockOutHandler) List(c *gin.Context) {
 	}
 	if kw := strings.TrimSpace(c.Query("keyword")); kw != "" {
 		like := "%" + kw + "%"
+		// keyword 同时命中：单号 / 往来单位 / 酒名（含全拼+首字母，反查含该酒明细的单据）。
+		// 酒名优先取 product 主数据、回退快照列；拼音只在 products 上（快照无拼音列）。
 		query = query.Where(
-			"order_no LIKE ? OR partner_id IN (SELECT id FROM partners WHERE shop_id = ? AND name LIKE ?)",
-			like, shopID, like,
+			"order_no LIKE ?"+
+				" OR partner_id IN (SELECT id FROM partners WHERE shop_id = ? AND name LIKE ?)"+
+				" OR id IN (SELECT it.order_id FROM stock_out_items it"+
+				"   LEFT JOIN products p ON p.id = it.product_id AND p.shop_id = it.shop_id"+
+				"   WHERE it.shop_id = ? AND it.deleted_at IS NULL"+
+				"     AND (COALESCE(NULLIF(p.name,''), it.product_name) LIKE ?"+
+				"          OR p.name_pinyin LIKE ? OR p.name_initials LIKE ?))",
+			like, shopID, like, shopID, like, like, like,
 		)
 	}
 	// 按商品编码反查单据：精确匹配，走 idx_so_items_shop_code(shop_id, product_code) 索引