widgets: Dial: deleting min or max breaks the widget

[ES-Alexander]

Bug description

Deleting one of the range values in the Dial configuration permanently breaks the widget, even if you then put a valid value in afterwards:

Screen.Recording.2025-02-24.at.8.01.34.pm.mov

Steps to reproduce

1. Delete the min or max of a dial widget
2. It's now no longer functional (even if you replace the value)

Primary pain point(s)

Dials can break when you're trying to configure them, and the only way to fix them is deletion.

Additional context

This was the cause of the reopening of #1678.

Prerequisites

• I have checked to make sure that a similar request has not already been filed or fixed.