feat(order): module foundation (#6399)

What:
Initial Order module foundation.
Basic models and methods to manage entites like in Cart Module

packages/order/integration-tests/utils/database.ts

@@ -0,0 +1,13 @@
+import { TestDatabaseUtils } from "medusa-test-utils"
+
+import * as Models from "@models"
+
+const mikroOrmEntities = Models as unknown as any[]
+
+export const MikroOrmWrapper = TestDatabaseUtils.getMikroOrmWrapper(
+  mikroOrmEntities,
+  null,
+  process.env.MEDUSA_FULFILLMENT_DB_SCHEMA
+)
+
+export const DB_URL = TestDatabaseUtils.getDatabaseURL()