oas: [4/n] improve oas schemas (#9064)

Improve oas schemas [4/n]

www/utils/generated/oas-output/schemas/AdminExchangeRequestResponse.ts

@@ -1,7 +1,7 @@
 /**
  * @schema AdminExchangeRequestResponse
  * type: object
- * description: SUMMARY
+ * description: The details of a requested exchange.
  * x-schemaName: AdminExchangeRequestResponse
  * required:
  *   - return
@@ -9,8 +9,10 @@
  *   - exchange
  * properties:
  *   return:
+ *     description: The associated return's details.
  *     $ref: "#/components/schemas/AdminReturn"
  *   order_preview:
+ *     description: A preview of the order once the exchange is applied.
  *     $ref: "#/components/schemas/OrderPreview"
  *   exchange:
  *     $ref: "#/components/schemas/AdminExchange"