Screensharing a part of the screen

### Description of the new feature / enhancement

A quick access utility to share a portion of your Ultrawide screen monitor for those who have 1080p screens would be a super useful addition to share a ultra wide in Teams or Zoom calls.

### Scenario when this would be used?

In teams/zoom/Webex/etc. calls to a share all applications in a zone of your UW or UHD screen.

### Supporting information

There are a few apps that do this. RegionToShare and Ultrawide Screen Share 2.0, but an integration with Fancy Zones would be awesome.

There are several discussions on this. This is one:
https://www.reddit.com/r/MicrosoftTeams/comments/vfhzsu/how_do_you_share_your_screen_when_you_have_an/?rdt=38293

Start by clarifying the intended integration with Fancy Zones and the expected behavior in Teams, Zoom, and Webex. Define which screen regions should be shareable and how the feature would signal completion; the issue names no files, tests, or entry points to inspect.

Written by the indexing model from the issue text.