feat(core-flows,types): cancel order changes workflow (#8035)

what:

- adds cancel order changes workflow

packages/modules/order/src/models/order-change.ts

@@ -211,7 +211,7 @@ export default class OrderChange {
     columnType: "timestamptz",
     nullable: true,
   })
-  canceled_at?: Date
+  canceled_at?: Date | null = null
 
   @Property({
     onCreate: () => new Date(),