apps/web/src/components/ChatView.tsx                        |  12 ---
 apps/web/src/components/Sidebar.tsx                         |  40 ++-------
 apps/web/src/components/sidebar/SidebarChrome.tsx           |   2 +
 apps/web/src/components/sidebar/SidebarThreadUndoNotice.tsx |  30 +++++++
 apps/web/src/components/ui/alert.tsx                        |   2 +
 apps/web/src/hooks/showThreadUndoNotice.test.ts             | 152 ++++++++++++++++++++++++++++++++
 apps/web/src/hooks/showThreadUndoNotice.ts                  | 106 ++++++++++++++++++++++
 apps/web/src/hooks/showUndoToast.test.ts                    | 127 --------------------------
 apps/web/src/hooks/showUndoToast.ts                         |  87 ------------------
 apps/web/src/hooks/threadUndo.ts                            |  19 +++-
 apps/web/src/hooks/useThreadActions.ts                      |  47 +++-------
 apps/web/src/hooks/useThreadActions.undo.test.ts            |  71 ++++++---------
 apps/web/src/routes/_chat.tsx                               |  14 +++
 docs/user/keybindings.md                                    |   9 +-
 14 files changed, 378 insertions(+), 340 deletions(-)