Make disabled state of Range input more obvious

## Component/pattern to amend

[Range Input](https://vanillaframework.io/docs/base/forms#range)

## Visual


## Context

I found the `disabled` Range input to be visually very similar to the non-disabled version because of the following reasons:

- The color for the `disabled` range input looks very similar to the non-disabled version.
- The pointer also does not change to the "not-allowed" or "default" state. It keeps being a "cursor" type.

In comparison other form inputs (like the [Checkbox](https://vanillaframework.io/docs/base/forms#checkbox)) change the color to gray and the cursor to "not-allowed" when the input is `disabled`.

Start with the linked Range Input component and compare its disabled presentation with the Checkbox behavior described in the issue. Done means the disabled range input is clearly distinct through a gray-like color and an appropriate non-interactive cursor.

Written by the indexing model from the issue text.