WIP: tooltip styling and sidebar tooltips

[marcinbauer-ohf]

Breaking change

None.

Proposed change

This draft PR captures ongoing work around tooltip styling and sidebar tooltips.
It experiments with moving sidebar item tooltips over to ha-tooltip and introduces surface and inverted surface tokens used by the tooltip styling.

Screenshots

Not included yet.
Please add screenshots or a short video before marking this ready for review because this PR changes visible tooltip and sidebar behavior.

Type of change

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

Additional information

• This PR fixes or closes issue: n/a
• This PR is related to issue or discussion: n/a
• Link to documentation pull request: n/a
• Link to developer documentation pull request: n/a
• Link to backend pull request: n/a

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
• There is no commented out code in this PR.
• I have followed the development checklist
• I have followed the perfect PR recommendations
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

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

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

To help with the load of incoming pull requests:

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