helix: Apply modification (e.g. switch case) on a single character only in helix mode (#38119)

Closes #34192

Without selection, only current character would be affected.

Also if #38117 is merged too, then transformations in SelectMode behave
correctly too and selection is not collapsed.

Release Notes:

- helix: Implemented `~`, `` ` ``, `` Alt-` `` correctly in normal and
select modes

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Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>
ed46e2ca77Romans Malinovskis committed on 9/18/2025, 8:47:15 AM· committed by GitHubparentd85a6db
2 files changedLine totals unavailable