Undo and redo actions are available for message edits

One mis-click on a delete button that wipes a forty-message research conversation is the kind of moment that ends a subscription. Destructive actions without undo treat every user gesture as final, which is wrong for a surface where the data is valuable, the buttons are dense, and mobile accidental taps are routine. A simple 5-second undo toast costs almost nothing to build and prevents the single worst user experience your product can produce.

Wrap every destructive action in an optimistic state update plus a toast with an "Undo" action and a 5-second duration. Keep the deleted record in memory during the window and re-insert at its original index on undo. For heavier flows (bulk clear), move to a two-step confirm dialog. Implement in src/lib/hooks/use-undoable-delete.ts.

toast('Message deleted', { action: { label: 'Undo', onClick: () => restore(deleted) }, duration: 5000 })