feat: add challenges to payout model

[tessstoddard]

Summary of Changes

Adds challenges to payout model and update model to use lombok getter/setters. And returns a 202 if challenges are present in the create payout response

Fixes # (issue)

Public API Additions/Changes

Adds challenges to payouts https://developer.mx.com/drafts/mdx/payout/#payouts-create-a-payout

Downstream Consumer Impact

This shouldn't have any impact since it's just adding new functionality.

How Has This Been Tested?

I pulled in these changes locally and ran the e2e tests and they all passed. I also verified that if the response has challenges that a 202 is returned

POST http://localhost:3015/globalcu/users/U-00ujqk7rkv4L6FFWK1d7/payouts

HTTP/1.1 202 
Content-Type: application/vnd.mx.mdx.v6+json;charset=UTF-8
Transfer-Encoding: chunked
Date: Fri, 31 Jan 2025 21:47:47 GMT

{
  "payout": {
    "challenges": [
      {
        "id": "an-id",
        "user_id": "U-00ujqk7rkv4L6FFWK1d7"
      }
    ],
    "user_id": "U-00ujqk7rkv4L6FFWK1d7"
  }
}

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works

[meotch]

Lombok makes java POJOs so much cleaner!