#1205: improve "broken UI" with settings dialog when app is scaled up

[davegarthsimpson]

Motivation

Settings dialog reported as visually unpleasing, and functionally impaired when scaling up the IDE.

Change description

Uses a fixed footer and overflow: auto for settings dialog content.

Reviewer checklist

• PR addresses a single concern.
• The PR has no duplicates (please search among the Pull Requests before creating one)
• PR title and description are properly filled.
• Docs have been added / updated (for bug fixes / features)

[kittaakos]

I've tried it, and I think this is a good solution in IDE2 👍

[francescospissu]

It works as expected 👍

[AlbyIanna]

The issue is spread across all the dialogs.

This PR fixes #1205, but doesn't solve the issue for other dialogs.

e.g.: the Select Board dialog

I believe we should solve it at the root. Here I made an experiment, but it raised some other scrolling issues, so I didn't open a PR.

[davegarthsimpson]

The issue is spread across all the dialogs.

This PR fixes #1205, but doesn't solve the issue for other dialogs.

I believe we should solve it at the root. Here I made an experiment, but it raised some other scrolling issues, so I didn't open a PR.

I would solve case by case, as the dialogs can vary greatly, we may want a different design / UX for each, e.g. it's clearly not nice if scrollable elements also have a scrollable parent.

We can create separate PRs for any other dialogs that are broken in the same way.