* feat: add menu item role `palette` and `header`
* adds comments
* refactors new role items to new item types
* docs: custom type
* docs: note types only available on mac 14+
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Co-authored-by: Samuel Maddock <smaddock@slack-corp.com>
* feat: add MenuItem.userAccelerator property
This allows folks to read the user-assigned accelerator that macOS users can provide in system preferences. Useful for showing in-app shortcut help dialogs, you need to know if the accelerator you provided is not being used in favor of a user assigned one.
* chore: update syntax
* chore: add safety check for command index being -1
