tui: playbook undo (C-x u) never reaches the daemon, then every later keystroke is silently dropped

[edwin-zvs]

Every Playbook edit in the TUI is streamed to the daemon by handle_playbook_key, which snapshots the buffer before the key and flushes the resulting anchored diff afterwards:

let before = self.playbook_popup.as_ref().map(|popup| popup.buffer.clone());
// ... dispatch ...
if let Some(before) = before {
    self.flush_playbook_live_edit(before).await;
}

(crates/cli/src/app/editor.rs ~lines 652 / 822 @ ad47152)

C-x u does not go through that path. It is a global KeyAction, and its handler calls the mutation directly:

UndoPlaybook => {
    self.undo_playbook_edit();
}

(crates/cli/src/app.rs ~line 12705 @ ad47152)

So the undo mutates the local buffer and is never sent. The buffers diverge — and they stay diverged, because the next keystroke's anchored diff is computed against a before the daemon never received. Its old_string no longer exists server-side, playbook.edit fails with old_string not found in the current playbook, and the failure is swallowed (#1089). Every keystroke after that fails the same way.

Repro

1. Open a Playbook in the TUI on a session whose document is in sync.
2. Type abc. Confirm the daemon has it (construct playbook get, or playbook.get over IPC).
3. Press C-x u.
4. Type Z.

Observed, against a daemon at v109:

step	daemon	TUI
type abc	v109 - build the thing …abc	…abc
C-x u	v109 …abc	…ab
type Z	v109 …abc (unchanged)	…abZ

From step 3 on, the document the agent and the web UI see is frozen. The only indication is the * modified chip in the pane title. C-x C-s recovers correctly (playbook merged with agent edits (version 42)), but nothing points the user at it.

The web UI's C-x u does sync — this is TUI-only.

Expected

Undo is an edit like any other and must reach the daemon.

Acceptance criteria

• C-x u in the Playbook publishes the resulting document to the daemon, so agents and other clients see it.
• After an undo, subsequent typing continues to sync (no silent divergence).
• C-/ (the in-editor alias, editor.rs ~line 763) and C-x u behave identically.
• Regression test: undo followed by a keystroke leaves client and daemon documents equal.

Found during a hands-on UX audit of the Playbook in the TUI and web UI.