feat(BE-34): extend DB schema and update master data APIs [partial]

✅ DB Schema: product_warehouse entity and migration
✅ Master Data: added filter params to getall APIs
🚧 Pending: stock_logs implementation and adjustment APIs

internal/modules/inventory/product-warehouses/validations/product_warehouse.validation.go

@@ -0,0 +1,21 @@
+package validation
+
+type Create struct {
+	ProductId   uint `json:"product_id" validate:"required,number,min=1"`
+	WarehouseId uint `json:"warehouse_id" validate:"required,number,min=1"`
+	Quantity    int  `json:"quantity" validate:"required,number,min=0"`
+}
+
+type Update struct {
+	ProductId   *uint `json:"product_id,omitempty" validate:"omitempty,number,min=1"`
+	WarehouseId *uint `json:"warehouse_id,omitempty" validate:"omitempty,number,min=1"`
+	Quantity    *int  `json:"quantity,omitempty" validate:"omitempty,number,min=0"`
+}
+
+type Query struct {
+	Page        int    `query:"page" validate:"omitempty,number,min=1"`
+	Limit       int    `query:"limit" validate:"omitempty,number,min=1,max=100"`
+	Search      string `query:"search" validate:"omitempty,max=50"`
+	ProductId   uint   `query:"product_id" validate:"omitempty,number,min=1"`
+	WarehouseId uint   `query:"warehouse_id" validate:"omitempty,number,min=1"`
+}