Mac: Fixes #13214: Markdown editor: Don't open links on ctrl-click

[personalizedrefrigerator]

Summary

Fixes #13214 by disabling the ctrl-click handler for links on MacOS.

Manual testing

MacOS

1. Add https://example.com/ to a note.
2. From the Markdown editor, cmd-click the just-added link. Verify that this opens example.com in a web browser.
3. Repeat step 1 for ctrl-click.
4. Add a checklist item to the note with - [ ] test.
5. Verify that cmd-click toggles the checklist item, but ctrl-click does not.
6. For testing, hardcode preferMacShortcuts to false, then restart the desktop app.
7. Verify that ctrl-click toggles the checklist item.
8. Verify that ctrl-click opens the in-note link.