Add Starlink reboot button

[boswelja]

Proposed change

Adding the button platform to Starlink, which allows users to reboot their starlink system from homeassistant.

Type of change

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

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request: Add Starlink documentation for button home-assistant.io#25710

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• 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

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.
• Untested files have been added to .coveragerc.

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[bdraco]

Tested 👍

[bdraco]

Unrelated to this PR, but are the units for elevation correct?

[boswelja]

Unrelated to this PR, but are the units for elevation correct?

It is documented as "elevation, in degrees", but since these aren't official docs from Starlink themselves it could be wrong. Do you suspect something is amiss?

[bdraco]

Unrelated to this PR, but are the units for elevation correct?

It is documented as "elevation, in degrees", but since these aren't official docs from Starlink themselves it could be wrong. Do you suspect something is amiss?

I would expect it to be called Altitude since it's in degrees but after digging in, Starlink calls it that so seems fine. Just an unexpected choice... but so is the Wi-Fi ap name