clarified the documentation to fix issue #15458

[nimishgautam]

Clarified the documentation around auto-shift for modifier keys.

Description

Auto-shift has a feature called RETRO_SHIFT that allows you to do a retro-tap-style auto-shift on modifier keys. However, you also have to add a custom function to enable retro shift per modifier key you want shifted. This is not at all clear from the docs, and is the reason this issue exists.

Types of Changes

• Core
• [x ] Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout/userspace (addition or update)
• [x ] Documentation

Issues Fixed or Closed by This PR

• issue [Bug] Retro Shift not working on Mod Tap keys #15458

Checklist

• My code follows the code style of this project: C, Python
• [x ] I have read the PR Checklist document and have made the appropriate changes.
• [x ] My change requires a change to the documentation.
• [ x] I have updated the documentation accordingly.
• [ x] I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• [ x] I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[IsaacElenbaas]

Duplicate of #15889 (here) which has some code fixes and is ready to go.

I don't like how small the note is there, but also don't want to restate what's outlined elsewhere in the docs and may change.

[stale]

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[github-actions]

Thank you for your contribution!
This pull request has been automatically marked as stale because it has not had activity in the last 45 days. It will be closed in 30 days if no further activity occurs. Please feel free to give a status update now, or re-open when it's ready.
For maintainers: Please label with bug, awaiting review, breaking_change, in progress, or on hold to prevent the issue from being re-flagged.

[github-actions]

Thank you for your contribution!
This pull request has been automatically closed because it has not had activity in the last 30 days. Please feel free to give a status update now, ping for review, or re-open when it's ready.
// [stale-action-closed]