feat(backend): 出入库编码搜索双路匹配+建单填快照；finance 趋势/日期区间；partner/product 拼音搜索

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JJ1g8XV1YhhmHRzhwWEW7o

backend/internal/handler/inventory.go

@@ -77,6 +77,11 @@ func (h *InventoryHandler) List(c *gin.Context) {
 		like := "%" + keyword + "%"
 		args = append(args, like, like, like, like)
 	}
+	// 商品编码独立筛选（库存屏工具栏第二个搜索框，对齐原型 codeInput）
+	if code := c.Query("code"); code != "" {
+		baseWhere += " AND COALESCE(NULLIF(p.code,''), NULLIF(sii.product_code,''), inv.product_code, '') LIKE ?"
+		args = append(args, "%"+code+"%")
+	}
 	if warehouseIDStr != "" {
 		baseWhere += " AND inv.warehouse_id = ?"
 		args = append(args, warehouseIDStr)
@@ -167,24 +172,41 @@ type inventorySummary struct {
 	InStockQty    float64 `json:"in_stock_qty"`   // 在库总数量
 	ShortageCount int64   `json:"shortage_count"` // 缺货数（qty<=0）
 	WarningCount  int64   `json:"warning_count"`  // 预警数（0<qty<安全库存）
+	// 月初快照（供 KPI 环比）：本月净变动由 inventory_logs 反推
+	LastMonthSku   int64   `json:"last_month_sku"`   // 月初存在的库存行数
+	LastMonthQty   float64 `json:"last_month_qty"`   // 月初在库总数量
+	LastMonthValue float64 `json:"last_month_value"` // 月初库存货值
 }
 
 // Summary GET /api/v1/inventory/summary —— 全店汇总（守多租户）
 func (h *InventoryHandler) Summary(c *gin.Context) {
 	shopID := middleware.GetShopID(c)
+	now := time.Now()
+	monthStart := time.Date(now.Year(), now.Month(), 1, 0, 0, 0, 0, now.Location())
+	// 月初数量 = 当前数量 − 本月净变动（product=序列号模型下 log 与库存行按 product_id+warehouse_id 一一对应）
 	const sql = `
 		SELECT
 		  COUNT(*) AS sku_count,
 		  COALESCE(SUM(inv.quantity * COALESCE(sii.unit_price, inv.unit_price, p.purchase_price)), 0) AS stock_value,
 		  COALESCE(SUM(inv.quantity), 0) AS in_stock_qty,
 		  COALESCE(SUM(CASE WHEN inv.quantity <= 0 THEN 1 ELSE 0 END), 0) AS shortage_count,
-		  COALESCE(SUM(CASE WHEN inv.quantity > 0 AND p.min_stock IS NOT NULL AND inv.quantity < p.min_stock THEN 1 ELSE 0 END), 0) AS warning_count
+		  COALESCE(SUM(CASE WHEN inv.quantity > 0 AND p.min_stock IS NOT NULL AND inv.quantity < p.min_stock THEN 1 ELSE 0 END), 0) AS warning_count,
+		  COALESCE(SUM(CASE WHEN inv.created_at < ? THEN 1 ELSE 0 END), 0) AS last_month_sku,
+		  COALESCE(SUM(CASE WHEN inv.created_at < ? THEN inv.quantity - COALESCE(lg.net, 0) ELSE 0 END), 0) AS last_month_qty,
+		  COALESCE(SUM(CASE WHEN inv.created_at < ? THEN (inv.quantity - COALESCE(lg.net, 0)) * COALESCE(sii.unit_price, inv.unit_price, p.purchase_price) ELSE 0 END), 0) AS last_month_value
 		FROM inventories inv
 		LEFT JOIN stock_in_items sii ON sii.id = inv.stock_in_item_id
 		LEFT JOIN products p ON p.id = inv.product_id AND p.deleted_at IS NULL
+		LEFT JOIN (
+		  SELECT product_id, warehouse_id,
+		         SUM(CASE WHEN direction = 'in' THEN quantity ELSE -quantity END) AS net
+		  FROM inventory_logs
+		  WHERE shop_id = ? AND created_at >= ?
+		  GROUP BY product_id, warehouse_id
+		) lg ON lg.product_id = inv.product_id AND lg.warehouse_id = inv.warehouse_id
 		WHERE inv.shop_id = ? AND inv.deleted_at IS NULL`
 	var s inventorySummary
-	if err := h.db.Raw(sql, shopID).Scan(&s).Error; err != nil {
+	if err := h.db.Raw(sql, monthStart, monthStart, monthStart, shopID, monthStart, shopID).Scan(&s).Error; err != nil {
 		util.RespondError(c, http.StatusInternalServerError, "QUERY_ERROR", "查询失败")
 		return
 	}