feat(medusa-js, medusa-react, medusa): Prepare API for admin implementations (#3110)

********What********
Add `joinSalesChannels util to stock locations

Add the following endpoints to medusa-react
- inventory items
    - mutations
        - update
        - delete
        - update location level
        - delete location level
        - create location level
    - queries
        - list inventory items
        - get inventory item
        - list location levels
- Stock locations
    - mutations
        - create stock location
        - update stock location
        - delete stock location
    - queries
        - list stock locations
        - get stock locatoin
- Variants
    - queries
        - get inventory
- Reservations
    - mutations
        - create reservation
        - update reservation
        - delete reservation
    - queries
        - list reservations
        - get reservation
- sales channels 
  - mutations
    - associate location with sc
    - remove location association

**Why**
- Update clients to reflect new api endpoints in the core with inventory modules

Co-authored-by: Philip Korsholm <88927411+pKorsholm@users.noreply.github.com>

packages/medusa/src/api/routes/admin/store/get-store.ts

@@ -1,11 +1,9 @@
-import { FulfillmentProvider, PaymentProvider, Store } from "../../../../models"
 import {
   FulfillmentProviderService,
   PaymentProviderService,
   StoreService,
 } from "../../../../services"
-import { FeatureFlagsResponse } from "../../../../types/feature-flags"
-import { ModulesResponse } from "../../../../types/modules"
+import { ExtendedStoreDTO } from "../../../../types/store"
 import { FlagRouter } from "../../../../utils/flag-router"
 import { ModulesHelper } from "../../../../utils/module-helper"
 
@@ -77,12 +75,7 @@ export default async (req, res) => {
 
   const data = (await storeService.retrieve({
     relations,
-  })) as Store & {
-    payment_providers: PaymentProvider[]
-    fulfillment_providers: FulfillmentProvider[]
-    feature_flags: FeatureFlagsResponse
-    modules: ModulesResponse
-  }
+  })) as ExtendedStoreDTO
 
   data.feature_flags = featureFlagRouter.listFlags()
   data.modules = modulesHelper.modules

packages/medusa/src/api/routes/admin/store/index.ts

@@ -1,6 +1,7 @@
 import { Router } from "express"
-import { PaymentProvider, Store, TaxProvider } from "./../../../../"
+import { PaymentProvider, TaxProvider } from "./../../../../"
 import middlewares from "../../../middlewares"
+import { ExtendedStoreDTO } from "../../../../types/store"
 
 const route = Router()
 
@@ -34,10 +35,10 @@ export default (app) => {
  * type: object
  * properties:
  *   store:
- *     $ref: "#/components/schemas/Store"
+ *     $ref: "#/components/schemas/ExtendedStoreDTO"
  */
 export type AdminStoresRes = {
-  store: Store
+  store: ExtendedStoreDTO
 }
 
 /**