Add background option to update/install APIs

[mdegat01]

Proposed change

Enable background update/install of Home Assistant and Addons. This way Home Assistant can listen in for progress updates on install/addon and present that to the user

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (which adds functionality to the supervisor)
• 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 Background option for install/update #6132
• This PR is related to issue:
• Link to documentation pull request: Document background addon install/update option developers.home-assistant#2775
• Link to cli pull request:
• Link to client library pull request: Add support for addon update/install in background home-assistant-libs/python-supervisor-client#177

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 Ruff (ruff format supervisor tests)
• Tests have been added to verify that the new code works.

If API endpoints or add-on configuration are added/changed:

• Documentation added/updated for developers.home-assistant.io
• CLI updated (if necessary)
• Client library updated (if necessary)

[home-assistant]

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[mdegat01]

@agners refactored to use a specific validation_complete asyncio.Event as an arg rather then looking for bus events.

[agners]

Nice, LGTM! I like this explicit synchronization using asyncio.Event much more.