Formstack-save and resume: no system feedback validation or error handling

## Describe the bug
As I'm delivering https://github.com/cityofaustin/techstack/issues/3686, I double-checked for error states since there's an input field and I didn't come across affordances for email validation, error messaging, and success confirmation.

## https://cityofaustin.formstack.com/forms/cprc_application

## To Reproduce
Steps to reproduce the behavior
example:
1. Go to 'https://cityofaustin.formstack.com/forms/cprc_application'
2. Click on `Save and resume later`
3. Input an erroneous email address like, `abcd@.com`
4. Page clears to all-white, with no system feedback

## Current behavior
No system feedback

## Expected behavior
- Email address validation to prevent user error
- Error messaging
- Success state confirmation. Inputting a correct email address did successfully send the email, but on the user's end, once the "Send save and resume link" button has been clicked there's no feedback that it was successfully sent.

## Screenshots

## Device and browser
I saw this error on Chrome and Firefox, but didn't try Safari.

## Additional context
- Users risk having to input information again, or believing that they've saved information that the system didn't record
- We risk making users unhappy, losing their confidence