Summary:
- Updates styling of form submitted page.
- Tweaks styling of checkboxes, labels, and questions on form page.
- Adds new form 404 page.
- Adds checkbox to not show warning again when publishing or un-publishing a form.
- Excludes formula, hidden, and attachment columns in submitted form data.
- Adds placeholder text to form configuration inputs.
- Improves dark mode styling in Form widget.
- Updates default title and description of new forms.
- Updates styling of Form widget buttons.
- Fixes form success text input handling.
Test Plan: Browser tests.
Reviewers: jarek
Reviewed By: jarek
Differential Revision: https://phab.getgrist.com/D4170
