Add 'focus' option to geo_location_sources for map card

[karwosts]

Proposed change

Map card entities have the focus option to exclude them from the auto-fit boundary, but geo_location_sources have no such option (so the fitBounds always wraps the entirety of all geo_location entities).

This PR adds the same focus option to geo_location_sources. As it is somewhat advanced (and not trivial to create UI for), the use of this option locks the card to yaml-only.

Can document on approval.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (thank you!)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example configuration

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue or discussion: https://community.home-assistant.io/t/map-card-force-the-home-as-the-center/786623/2
• Link to documentation pull request: Update map.markdown for geolocation focus option home-assistant.io#35454

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

[MindFreeze]

Having yaml only options is fine but we don't need to lock the card in yaml mode. The editor should handle the new object format and just not display the new option

[ildar170975]

@karwosts
If geo location sources provide unavailable data and a zone is not home - then the Map card will show a home area due to #20722.

[karwosts]

The editor should handle the new object format and just not display the new option

OK I updated to make this feature remain compatible with visual editor.

[MindFreeze]

LGTM but please document it

[karwosts]

docs added