feat: 财务结清、酒行信息、库存备注编辑、标签溯源、入库必填校验

后端
- 新增 shop handler：GET/PUT /shop/info（管理员权限）
- 新增 finance CloseByRef：按单据 ref_type+ref_id 结清账款
- 新增 inventory UpdateRemark：PUT /inventory/:id/remark
- 入库/出库审批自动生成财务应付/应收记录（去除金额>0限制）
- 种子数据 S001-S003 补充真实门店信息

前端
- 设置页新增「酒行信息」Tab，管理员可编辑门店名称/地址/电话/负责人
- 入库单列表新增结清按钮（含确认弹窗），出库单同步
- 入库表单：规格、系列、生产日期、供应商、商品名称改为提交必填
- 入库/出库列表新增入库时间、出库时间、创建时间列
- 商品标签标题改为读取 shop 表门店名，扫码文案改为「扫码溯源 · TRACE」
- 标签页脚显示门店地址和电话（从 API 读取，不再依赖编译时 dart-define）
- 库存备注支持点击编辑，超4字截断显示+Hover展示全文
- ApiClient 新增 patch() 方法（已改用 PUT 规避 CORS）

文档
- 新增 docs/user-manual.md 完整用户操作手册（12章）

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/cmd/seed/main.go

@@ -666,37 +666,65 @@ func createStockOutOrder(
 
 func updateInventoryBatch(db *gorm.DB, shopID, whID, opID uint64, r stockInResult) {
 	for _, it := range r.items {
-		var inv model.Inventory
-		db.Where("shop_id = ? AND warehouse_id = ? AND product_id = ?", shopID, whID, it.productID).First(&inv)
-		before := inv.Quantity
-		after := before + it.qty
-		if inv.ID == 0 {
-			inv = model.Inventory{ShopID: shopID, WarehouseID: whID, ProductID: it.productID, Quantity: after}
-			db.Create(&inv)
-		} else {
-			db.Model(&inv).Update("quantity", after)
+		var qtyBefore float64
+		db.Model(&model.Inventory{}).
+			Where("shop_id = ? AND warehouse_id = ? AND product_id = ? AND deleted_at IS NULL", shopID, whID, it.productID).
+			Select("COALESCE(SUM(quantity), 0)").Scan(&qtyBefore)
+
+		productIDCopy := it.productID
+		whIDCopy := whID
+		inv := model.Inventory{
+			ShopID:      shopID,
+			WarehouseID: &whIDCopy,
+			ProductID:   &productIDCopy,
+			Quantity:    it.qty,
 		}
+		db.Create(&inv)
+
 		db.Create(&model.InventoryLog{
 			ShopID: shopID, WarehouseID: whID, ProductID: it.productID,
-			Direction: "in", Quantity: it.qty, QtyBefore: before, QtyAfter: after,
+			Direction: "in", Quantity: it.qty, QtyBefore: qtyBefore, QtyAfter: qtyBefore + it.qty,
 			RefType: "stock_in", RefID: r.order.ID, OperatorID: &opID,
 		})
 	}
 }
 
 func deductInventoryBatch(db *gorm.DB, shopID, whID, opID uint64, r stockOutResult) {
+	now := time.Now()
 	for _, it := range r.items {
-		var inv model.Inventory
-		db.Where("shop_id = ? AND warehouse_id = ? AND product_id = ?", shopID, whID, it.productID).First(&inv)
-		before := inv.Quantity
-		after := before - it.qty
+		var qtyBefore float64
+		db.Model(&model.Inventory{}).
+			Where("shop_id = ? AND warehouse_id = ? AND product_id = ? AND deleted_at IS NULL", shopID, whID, it.productID).
+			Select("COALESCE(SUM(quantity), 0)").Scan(&qtyBefore)
+
+		// FIFO deduction
+		var batches []model.Inventory
+		db.Where("shop_id = ? AND warehouse_id = ? AND product_id = ? AND quantity > 0 AND deleted_at IS NULL",
+			shopID, whID, it.productID).
+			Order("created_at ASC").Find(&batches)
+
+		remaining := it.qty
+		for i := range batches {
+			if remaining <= 0 {
+				break
+			}
+			b := &batches[i]
+			if b.Quantity <= remaining {
+				remaining -= b.Quantity
+				db.Model(b).Updates(map[string]interface{}{"quantity": 0, "deleted_at": now})
+			} else {
+				db.Model(b).Update("quantity", gorm.Expr("quantity - ?", remaining))
+				remaining = 0
+			}
+		}
+
+		after := qtyBefore - it.qty
 		if after < 0 {
 			after = 0
 		}
-		db.Model(&inv).Update("quantity", after)
 		db.Create(&model.InventoryLog{
 			ShopID: shopID, WarehouseID: whID, ProductID: it.productID,
-			Direction: "out", Quantity: it.qty, QtyBefore: before, QtyAfter: after,
+			Direction: "out", Quantity: it.qty, QtyBefore: qtyBefore, QtyAfter: after,
 			RefType: "stock_out", RefID: r.order.ID, OperatorID: &opID,
 		})
 	}