Get a user by ID with their role assignments

Example response

{
  "success": true,
  "data": {
    "id": "123e4567-e89b-12d3-a456-426614174001",
    "email": "user@example.com",
    "first_name": "John",
    "last_name": "Doe",
    "default_partner_id": "123e4567-e89b-12d3-a456-426614174001",
    "default_merchant_id": "123e4567-e89b-12d3-a456-426614174001",
    "created_at": "2024-03-19T12:00:00Z",
    "updated_at": "2024-03-19T12:00:00Z",
    "role_assignments": [
      {
        "id": "123e4567-e89b-12d3-a456-426614174001",
        "role": "global:admin",
        "created_at": "2024-03-19T12:00:00Z"
      }
    ]
  }
}