The undo/redo confirmation dialog capped at 60 columns and wrapped
even a short insert on wide terminals, showed a lowercase "snapshot
taken", a raw ISO-8601 timestamp, and lowercase yes/no labels.
Grow the dialog to fit its longest line (bounded 34–100), capitalise
Snapshot/Yes/No, and render the snapshot timestamp in local time,
human-formatted (24 May 2026, 11:00) via a new chrono dependency
(clock feature only; English month names). Yes/No capitalisation also
applies to the rebuild-confirm dialog.