Feat(order): order changes (#6435)

What:
 - Order DB schema migration
 - BigNumberField Decorator
  
![order_schema](https://github.com/medusajs/medusa/assets/37986729/64ec82ca-5c28-46ef-9a57-614c5a4d25f6)

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

@@ -0,0 +1,140 @@
+import { DAL } from "@medusajs/types"
+import {
+  OrderChangeStatus,
+  createPsqlIndexStatementHelper,
+  generateEntityId,
+} from "@medusajs/utils"
+import {
+  BeforeCreate,
+  Cascade,
+  Collection,
+  Entity,
+  Enum,
+  ManyToOne,
+  OnInit,
+  OptionalProps,
+  PrimaryKey,
+  Property,
+} from "@mikro-orm/core"
+import { OneToMany } from "typeorm"
+import Order from "./order"
+import OrderChangeAction from "./order-change-action"
+
+type OptionalLineItemProps = DAL.EntityDateColumns
+
+const OrderIdIndex = createPsqlIndexStatementHelper({
+  tableName: "order_change",
+  columns: "order_id",
+})
+
+const OrderChangeStatusIndex = createPsqlIndexStatementHelper({
+  tableName: "order_change",
+  columns: "status",
+})
+
+@Entity({ tableName: "order_change" })
+export default class OrderChange {
+  [OptionalProps]?: OptionalLineItemProps
+
+  @PrimaryKey({ columnType: "text" })
+  id: string
+
+  @Property({ columnType: "text" })
+  @OrderIdIndex.MikroORMIndex()
+  order_id: string
+
+  @ManyToOne({
+    entity: () => Order,
+    fieldName: "order_id",
+    cascade: [Cascade.REMOVE, Cascade.PERSIST],
+  })
+  order: Order
+
+  @OneToMany(() => OrderChangeAction, (action) => action.order_change_id, {
+    cascade: [Cascade.REMOVE],
+  })
+  actions = new Collection<OrderChangeAction>(this)
+
+  @Property({
+    columnType: "text",
+    nullable: true,
+  })
+  description: string | null = null
+
+  @Enum({ items: () => OrderChangeStatus, default: OrderChangeStatus.PENDING })
+  @OrderChangeStatusIndex.MikroORMIndex()
+  status: OrderChangeStatus
+
+  @Property({ columnType: "text", nullable: true })
+  internal_note: string | null = null
+
+  @Property({ columnType: "text" })
+  created_by: string // customer, user, third party, etc.
+
+  @Property({ columnType: "text", nullable: true })
+  requested_by: string | null = null // customer or user ID
+
+  @Property({
+    columnType: "timestamptz",
+    nullable: true,
+  })
+  requested_at?: Date
+
+  @Property({ columnType: "text", nullable: true })
+  confirmed_by: string | null = null // customer or user ID
+
+  @Property({
+    columnType: "timestamptz",
+    nullable: true,
+  })
+  confirmed_at?: Date
+
+  @Property({ columnType: "text", nullable: true })
+  declined_by: string | null = null // customer or user ID
+
+  @Property({ columnType: "text", nullable: true })
+  declined_reason: string | null = null
+
+  @Property({ columnType: "jsonb", nullable: true })
+  metadata: Record<string, unknown> | null = null
+
+  @Property({
+    columnType: "timestamptz",
+    nullable: true,
+  })
+  declined_at?: Date
+
+  @Property({ columnType: "text", nullable: true })
+  canceled_by: string | null = null
+
+  @Property({
+    columnType: "timestamptz",
+    nullable: true,
+  })
+  canceled_at?: Date
+
+  @Property({
+    onCreate: () => new Date(),
+    columnType: "timestamptz",
+    defaultRaw: "now()",
+  })
+  created_at: Date
+
+  @Property({
+    onCreate: () => new Date(),
+    onUpdate: () => new Date(),
+    columnType: "timestamptz",
+    defaultRaw: "now()",
+  })
+  updated_at: Date
+
+  @BeforeCreate()
+  onCreate() {
+    this.id = generateEntityId(this.id, "ordch")
+  }
+
+  @OnInit()
+  onInit() {
+    this.id = generateEntityId(this.id, "ordch")
+  }
+}