Custom appsAPIPOST /validate

This endpoint performs account validation when setting up an account for the app. The incoming payload includes information about the account type to be validated and all fields required:

{
    "id": "basic", // identifier for the account type
    "fields": { //list of field values to validate according to schema
    	"username": "test_user",
        "password": "test$user!",
        /*...*/
    }
}

If the account is valid, the app should return HTTP status 200 with a JSON object containing a friendly name for the account:

{"name": "Awesome Account"}

If the account is invalid, the app should return HTTP status 401 (Not Authorized) with a simple JSON object containing an error message:

{"error": "Your password is incorrect!"}