fix(core): restore platform-aware keyboard shortcuts

[rexxars]

Description

Seems the facelift PR caused a regression that basically reverted this PR in terms of end result.

This PR reverts to using the <Hotkeys> component from the sanity core, which is platform aware.

What to review

• Shows Ctrl + Option + P on publish and similar, when on Mac
• Shows Ctrl + Alt + P on publish and similar, when not on Mac

(This should be uncovered by the test suite, fwiw)

Testing

I added one test for this in the publish action. Ideally I would test all the different locations that use any kind of hotkeys that may involve the Alt key, but that would be a lot of tests in a lot of different places. I may introduce an ESLint rule to disallow the use of <Hotkeys> from @sanity/ui later.

Notes for release

• Fixes a regression causing platform-aware hotkeys not to be displayed in tooltips