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/utils/src/dal/index.ts

@@ -1,3 +1,4 @@
+export * from "./mikro-orm/big-number-field"
 export * from "./mikro-orm/mikro-orm-create-connection"
 export * from "./mikro-orm/mikro-orm-repository"
 export * from "./mikro-orm/mikro-orm-soft-deletable-filter"

packages/utils/src/dal/mikro-orm/big-number-field.ts

@@ -0,0 +1,78 @@
+import { BigNumber } from "../../totals/big-number"
+
+const bigNumberFields = new WeakMap<
+  object,
+  { prop: string; options: { nullable?: boolean } }[]
+>()
+
+export function BigNumberField(options: { nullable?: boolean } = {}) {
+  return function (target: any, prop: string) {
+    const entity = target.constructor
+    if (!bigNumberFields.has(entity)) {
+      bigNumberFields.set(entity, [])
+    }
+
+    if (prop.startsWith("raw_")) {
+      const suggestedPropName = prop.replace("raw_", "")
+      throw new Error(
+        `BigNumberField decorator has to be used on the property "${suggestedPropName}" and ${prop} typed as BigNumberRawValue.`
+      )
+    }
+
+    bigNumberFields.get(entity)?.push({ prop, options })
+
+    if (!entity.prototype.__bigNumberInitialized) {
+      entity.prototype.__bigNumberInitialized = true
+
+      registerGlobalHook(entity)
+    }
+  }
+}
+
+function registerGlobalHook(entity: any) {
+  const originalOnInit = entity.prototype.onInit
+  const originalOnCreate = entity.prototype.onCreate
+  const originalOnUpdate = entity.prototype.onUpdate
+
+  entity.prototype.onInit = function (...args: any[]) {
+    initializeBigNumberFields(this)
+
+    if (originalOnInit) {
+      originalOnInit.apply(this, args)
+    }
+  }
+
+  entity.prototype.onCreate = function (...args: any[]) {
+    initializeBigNumberFields(this)
+
+    if (originalOnCreate) {
+      originalOnCreate.apply(this, args)
+    }
+  }
+
+  entity.prototype.onUpdate = function (...args: any[]) {
+    initializeBigNumberFields(this)
+
+    if (originalOnUpdate) {
+      originalOnUpdate.apply(this, args)
+    }
+  }
+}
+
+function initializeBigNumberFields(entity: any) {
+  const fields = bigNumberFields.get(entity.constructor) ?? []
+
+  for (const field of fields) {
+    const { prop, options } = field
+
+    const rawValue = entity[`raw_${prop}`]
+    const value = entity[prop]
+    if (options.nullable && rawValue === null && value === null) {
+      return
+    }
+
+    const val = new BigNumber(rawValue ?? value)
+    entity[prop] = val.numeric
+    entity[`raw_${prop}`] = val.raw
+  }
+}