deployer(ET): auto-commit from deployer run_id=503

Review P1: a STOP while a self-hosting task is PARKED on `deploy` awaiting the
manual `Confirm Deploy` was classified as a critical merge/deploy window solely
because the task still held the per-repo merge-lease (held from merge-gate through
deploy->done). That window is fully reversible — nothing is merged or deployed yet
(the irreversible merge_pr runs later in _handle_merge_verify, always under an
INITIATED marker). So the cancel was DEFERRED to run_deploy_finalizer, which only
runs after Phase B (Confirm Deploy) — the very step the operator pressed STOP to
avoid. Result: the deferred cancel was never applied, the task wedged non-terminal
holding the lease, blocking the repo's serial-gate (ORCH-088) and merges.

Fix: gate the merge-lease branch of cancel.in_critical_window on an actively
RUNNING actor (_task_has_running_actor). Lease held + running deploy/merge job ->
still deferred (genuine in-flight step). Lease held + no running actor (idle
deploy parking) -> NOT critical -> immediate full reset, which itself releases the
lease (step 3c) and drives the task terminal. INITIATED-marker deferral unchanged.

Also fixes review P2 (AC-6): set_task_cancel_requested now returns the first-stamp
fact (rowcount), and the deferred branch only notifies on the first transition —
a repeated STOP while still deferred no longer spams duplicate notifications.

Tests: test_d7_lease_held_idle_parking_is_not_critical,
test_d7_lease_held_with_running_actor_still_critical,
test_d7_stop_on_deploy_awaiting_confirm_full_resets,
test_d7_repeated_stop_in_critical_window_no_duplicate_notify. Full suite green (1349).

Refs: ORCH-090

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/work-items/ORCH-090/14-deploy-log.md

@@ -1,12 +0,0 @@
----
-deploy_status: SUCCESS
-work_item: ORCH-090
-hook_exit_code: 0
-deployed_by: deploy-finalizer
----
-
-# Deploy log — ORCH-036 executable self-deploy
-
-Прод-деплой завершён хост-хуком с exit-code `0` -> `deploy_status: SUCCESS`.
-
-Вердикт зафиксирован детерминированным finalizer'ом (Фаза C), не LLM.

docs/work-items/ORCH-090/16-post-deploy-log.md

@@ -1,14 +0,0 @@
----
-post_deploy_status: HEALTHY
-action_taken: NONE
-work_item: ORCH-090
-window_s: 900
-checks_total: 30
-checks_failed: 0
----
-
-# Post-deploy log — ORCH-021 post-deploy monitor
-
-Наблюдение прода завершено: `post_deploy_status: HEALTHY`, `action_taken: NONE`.
-
-Окно наблюдения: 900s; опросов всего: 30, из них с провалом: 0.