feat: extend the silent-until-signal heartbeat to the two MCP monitor loops

Auto triage-intake and auto inbox-zero now collapse an empty check to a single "<workflow> at HH:MM: nothing" line, matching the sentry quiet-fire heartbeat from Phase 1. Detection stays in-session, so the MCP-auth sources are scanned in full and only the output collapses. Inbox already had an acknowledge-only-on-empty rule, now unified to the standard format; triage's three-section sweep output gains the empty-sweep collapse.

Completes the silent-until-signal spec (Phases 2-5): the spec is the shared-policy home the three workflows reference, and a manual-testing entry covers the live-loop verification. Spec flipped to IMPLEMENTED.

1 files changed, 2 insertions, 2 deletions

diff --git a/.ai/workflows/inbox.org b/.ai/workflows/inbox.org
index 123e6df..fc8091b 100644
--- a/.ai/workflows/inbox.org
+++ b/.ai/workflows/inbox.org
@@ -482,14 +482,14 @@ A recurring, *interactive* roam check. Trigger phrase: "auto inbox zero" (match
 ** Per cycle
 
 1. Run roam mode's scan (Phase A local check + Phase B roam scan), read-only — no =git pull=. The capture-guard still gates any write: use =capture-guard --wait= (core §5) so a transient capture clears itself; if it's still open after the wait, *defer this cycle's roam reconcile to the next cycle* rather than surfacing — the loop cadence is the retry, and the filed items get swept next time. The rare write hands its git to =roam-sync= (roam Phase D).
-2. *Nothing found* → no inbox summary. One acknowledgement line: =ran at HH:MM, nothing found=. Nothing else. The acknowledge-only-on-empty rule keeps a quiet inbox quiet.
+2. *Nothing found* → no inbox summary. One heartbeat line: =inbox zero at HH:MM: nothing= (HH:MM local, from =date=) — the silent-until-signal policy, see =docs/specs/2026-07-20-silent-until-signal-monitors-spec.org=. Nothing else. Keeping a quiet inbox quiet is the whole point.
 3. *Items found* → summarize the found items, file them as tasks (roam Phase C), and *append them to a displayed queue* — the harness task list, via =TaskCreate= — so the queue accumulates across cycles. Then ask: "run this batch next?"
    - *Yes* → chain into =work-the-backlog.org= as an explicit second step after routing completes: pass it the eligibility query over the queued items (status =TODO= + =:solo:= per the scheme header, priority-ordered), =file-only= mode, paging off, cap 1. The highest-priority eligible candidate runs; the rest wait for the next tick or a later yes.
    - *No* → they stay queued for a later go.
    This mode never implements anything itself — routing ends here, and the execution loop lives in =work-the-backlog.org=, its one home.
 4. *Cross-cycle dedup.* Subsequent cycles add only *newly-found* items to the same displayed queue, never re-surfacing what's already there. Dedup against the queue (the =TaskCreate= list), not against what's already been implemented — a find that was queued-but-not-yet-run must not reappear, and one already filed into =todo.org= is dropped by roam Phase C's status check.
 
-A find is always surfaced and filed; execution happens only through the =work-the-backlog.org= chain and waits for Craig's yes. A quiet inbox produces only the timestamped acknowledgement. =auto inbox zero= is inherently in-session because its chain step waits for that yes.
+A find is always surfaced and filed; execution happens only through the =work-the-backlog.org= chain and waits for Craig's yes. A quiet inbox produces only the =inbox zero at HH:MM: nothing= heartbeat. =auto inbox zero= is inherently in-session because its chain step waits for that yes.
 
 ** Fully-unattended pass (=/schedule=) — vNext, not v1