feat(medusa): categories can be ranked based on position (#3341)

* chore: categories can be ranked based on position

* chore: fix tests

* chore: sort categories by order

* chore: fix bug where mpath relationship is messed up

* chore: enable linting - lint changes

* Update packages/medusa/src/repositories/product-category.ts

Co-authored-by: Frane Polić <16856471+fPolic@users.noreply.github.com>

* chore: fixed specs

* chore: cleanup repository to new typeorm interfaces + cleanup

* chore: revert repository changes due to incorrect sql

* chore: addressed pr reviews

---------

Co-authored-by: Frane Polić <16856471+fPolic@users.noreply.github.com>
Co-authored-by: adrien2p <adrien.deperetti@gmail.com>

packages/medusa/src/models/product-category.ts

@@ -17,6 +17,7 @@ import {
 
 @Entity()
 @Tree("materialized-path")
+@Index(["parent_category_id", "rank"], { unique: true })
 export class ProductCategory extends SoftDeletableEntity {
   static productCategoryProductJoinTable = "product_category_product"
   static treeRelations = ["parent_category", "category_children"]
@@ -51,6 +52,9 @@ export class ProductCategory extends SoftDeletableEntity {
   @TreeChildren({ cascade: true })
   category_children: ProductCategory[]
 
+  @Column({ nullable: false, default: 0 })
+  rank: number
+
   @ManyToMany(() => Product, { cascade: ["remove", "soft-remove"] })
   @JoinTable({
     name: ProductCategory.productCategoryProductJoinTable,
@@ -119,6 +123,10 @@ export class ProductCategory extends SoftDeletableEntity {
  *     type: boolean
  *     description: A flag to make product category visible/hidden in the store front
  *     default: false
+ *   rank:
+ *     type: integer
+ *     description: An integer that depicts the rank of category in a tree node
+ *     default: 0
  *   category_children:
  *     description: Available if the relation `category_children` are expanded.
  *     type: array