fix(session): answer Claude Code 2.1.252's reversed folder-trust dialog

Every claude session in a directory claude had not seen before died about six
seconds after it started (`Pane is dead (status 1)`), before the agent drew a
composer. Reproduced on a fresh case and measured.

Claude Code 2.1.252 rewrote the dialog. It used to be

  ❯ 1. Yes, I trust this folder
    2. No, exit

and is now unnumbered, reversed, and highlights the option that quits:

  ❯ No, exit
    Yes, I trust this folder

Detection still worked (the confirm affordance carries the match once the
numbered option text is gone), so the failure was entirely in the answer: the
auto-accept pressed Enter on the highlighted default, which is now exit.

trustDialogNextKey() reads the ❯ marker off the rendered pane and returns ONE
keystroke at a time: an arrow while the cursor is on the wrong option, Enter
only once the screen shows it on the trust option, and null for a frame that
does not say. Both layouts are handled, and which way the trust option lies is
read from the frame rather than assumed, so a further reordering costs a
repaint instead of a session. The last marked option wins, because the
direct-PTY fallback reads an append-only buffer where an older frame must not
out-vote the freshest one.

Two things only a live pane showed:

- The scan ran solely from the PTY onData handler. The arrow that moves the
  cursor is the last output the pane produces, so the first fix parked every
  session with the cursor sitting on the right option and no Enter ever sent.
  It now schedules its own follow-up read (_trustDialogTimer, cleared in
  _clearAllTimers()), offset past the scan throttle so the chain cannot break
  on a boundary.
- The keystroke cap goes 3 -> 6, since answering is no longer one press.

The bundled codeman skill had the same blind \r as its bounded fallback, so
preamble 1.21.0 replaces it with _trust_key/_accept_trust: read
terminal?full=1, steer onto the trust option, re-read, then confirm. Those
keystrokes go out under their own clientId, because input sequence numbers are
monotonic per client and spending prompt numbers on dialog keys would make the
next send-and-wait look like a stale duplicate and vanish while reporting
success. The readiness recipes in docs/extending-codeman.md,
docs/api-reference.md and the skill's own reference carry the corrected answer,
plus a symptom-table entry for a worker whose pane is dead seconds after spawn.

Verified live on an isolated instance (own data dir and tmux socket): fresh
case -> arrow at 5 s -> Enter at 7 s -> composer, with hasTrustDialogAccepted
recorded. With the server-side auto-accept disabled in a throwaway copy, the
skill's fallback cleared a genuinely parked dialog in 1.1 s and spawn_worker
took a brand-new case to a live composer in 7.2 s; spawn_workers + sendwait +
last_text then ran end to end.

docs/api-reference.md

@@ -204,11 +204,16 @@ turn.
 The reliable sequence is: poll `GET /api/v1/sessions/:id` until `.data.pid` is
 non-null, then `wait-output` for the composer's own marker (`bypass`, the status
 bar of a CLI spawned in bypass mode) with a short timeout, handling the trust
-dialog only as the bounded fallback (`trust` matched → send `\r` → wait for
-`bypass` again). Do not probe `trust` first and Enter blindly: the dialog text
-stays in the terminal buffer for the life of the session, so a `trust` probe with
-`from=buffer` keeps matching on every later run and the Enter lands in a ready
-composer. A worked version is in
+dialog only as the bounded fallback.
+
+⚠️ **The fallback is not a bare `\r`.** Claude Code 2.1.252 unnumbered the dialog's
+options, reversed them and highlights `No, exit`, so an Enter sent blind quits the
+CLI and the pane dies seconds after the spawn. Read the `❯` marker off the current
+frame (`GET /api/v1/sessions/:id/terminal?full=1`), send `ESC [ B` while it is on
+`No, exit`, re-read, and confirm only once it is on `Yes, I trust this folder`.
+Reading the current frame is also what keeps this correct on later runs: the dialog
+text stays in the terminal buffer for the life of the session, so a `trust` probe
+with `from=buffer` keeps matching long after the dialog is gone. A worked version is in
 [`extending-codeman.md`](extending-codeman.md#seam-3-http-api-and-cli).
 
 ### `GET /api/v1/sessions/:id/wait`