v1.91.266.0 feat(pr-wait): gstack-pr-wait event watcher (tstack pr-wait design port) and /land-and-deploy Step 3 wiring (#3495)

* feat(pr-wait): gstack-pr-wait event watcher (tstack pr-wait design port) and /land-and-deploy Step 3 wiring

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* fix(pr-wait): keep the result codes in lib/result-codes-release.ts so fixtures that copy the module list keep working

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* test(pr-wait): function declarations for the fake-gh helpers so the pregate TSX import scanner maps the lib files

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* fix(pr-wait): /ship review pass 1 — every check gates green, --timeout, bot identity, signal disposition

Red Team and specialist findings on #3495, all fixed in the diff:

- green gates on every check on the head, as gstack-ci-gate does, so
  land-and-deploy Step 2 and Step 3 can no longer disagree while a
  non-required check pends; required checks still gate before they appear
- --timeout MINUTES (default 60, 0 = none) ends a watch that met nothing as
  PR_WAIT_BLOCKED naming the still-pending checks; restores Step 3's cap
- a bot owns logins that start with its name (greptile-apps[bot]), not any
  login containing it; a failed gating-bot check is a failed check, never a
  completed review
- ready: green alone when no gating bot is configured (pr_wait_gating_bots
  none no longer polls forever); held while merge state is UNKNOWN
- BEHIND and DIRTY announced once per head, with the short head in the line
- the bin installs no signal handlers: the synchronous loop never ran them
  and they made the process ignore SIGTERM/SIGINT; default disposition kills
  it at once and the next watcher takes over the dead pid's lock
- a gh spawn timeout (ETIMEDOUT) is retried like any transient failure
- a local fault (unwritable state root) is PR_WAIT_REFUSED exit 2, so exit 1
  always carries a PR_WAIT_BLOCKED line
- control characters in GitHub text never start a second event line

Tests: 21 new cases including a real SIGTERM against the bin, gstack-config
set-time validation and default parity, and the 14 state-matrix cells the
state-machines specialist listed (gstack-state-matrix check: ok, 33/33).

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* fix(pr-wait): /ship review pass 2 — advisory checks gate too, BEHIND keyed on the head, verdict survives a failed save

- an advisory bot's review is never waited for, but its check gates like any
  other, so gstack-ci-gate (Step 2) and gstack-pr-wait --until green (Step 3)
  read the same check set with no exception
- BEHIND and DIRTY are keyed on the head alone; the pass-1 key also held the
  base oid, so a base that kept moving re-announced BEHIND to a restarted
  watcher on every commit
- finish() keeps the printed verdict's exit code when the state file cannot
  be written; the save error goes to stderr
- PR_WAIT_BLOCKED and PR_WAIT_REFUSED summaries name every exit-1 and exit-2
  path (--timeout, a local error); emitBots docstring matches the gating rule
- CHANGELOG says what a timeout means at land-and-deploy Step 3: a STOP with
  the pending checks named, no wait-more question

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