On screens ≥600dp, Notes and Chat show a two-pane layout:
- Left pane (300dp): scrollable list with selection highlight
- Right pane: inline detail (NoteDetailScreen / ChatScreen)
Tapping a list item selects it in wide mode instead of pushing a route.
Creating a new conversation on wide screen auto-selects it in the pane.
Deleting a selected note/conversation clears the right pane.
NoteDetailScreen gains an optional onDeleted callback used by the
embedded pane to clear selection rather than call context.pop().
Tasks keep push-based navigation (edit form has save/pop semantics
that require a full-screen context).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>