Set individual users' AI credit limits

<Note> **Organization Admin** permissions are required to use this endpoint. </Note>

Set individual users' AI credit limits in bulk. Each entry names a user and either sets an individual limit or removes one so the user follows the organization default. All entries are applied in a single transaction.

{
  "users": [
    {
      "creditLimit": 50,
      "userId": "f4a2b3c8-0d1e-4f5a-9b6c-7d8e9f0a1b2c"
    }
  ]
}

{
  "users": [
    {
      "creditLimit": 50,
      "userId": "f4a2b3c8-0d1e-4f5a-9b6c-7d8e9f0a1b2c"
    }
  ]
}