support multi-module (#4)

* add multimodule
* re-package modules

server/internal/repo/repo_export_test.go

@@ -0,0 +1,15 @@
+package repo
+
+import (
+	"galaxy/model/order"
+
+	"github.com/google/uuid"
+)
+
+func LoadOrder_T(s Storage, t uint, id uuid.UUID) (*order.Order, bool, error) {
+	return loadOrder(s, t, id)
+}
+
+func SaveOrder_T(s Storage, t uint, id uuid.UUID, o *order.Order) error {
+	return saveOrder(s, t, id, o)
+}