chore(loop): move tasks to terminal states on GitHub gate events

[Alex1990]

Fixes the gap that would have stranded every loop PR from here on.

D30 — gate events recorded the metric but never moved the task

handleMetrics appended to metrics/acceptance.jsonl and returned:

const wrote = await appendAcceptance(S, row);
return { state: 'metrics', wrote, row };     // <- the task was never touched

So a loop PR that merged was counted for the auto-acceptance rate while its task sat in waiting-merge — contradicting the state machine ops.md defines (waiting-merge → accepted | rejected). Sweep cannot repair it either: sweep reconciles by listing open GitHub items, which by construction cannot see a closure. A loop PR merged unattended would keep showing under "Awaiting human merge" forever.

This was not hypothetical: it is the next thing A1 would have done. It went unnoticed only because #36/#37/#38 stalled at waiting-human (triaged, never reaching waiting-merge), and #28/#30/#33 were reconciled by hand during A0.

The fix

handleMetrics now applies the transition too, via markTaskTerminal:

Event	Task moves to
merged	accepted
closed-unmerged	rejected
released	unchanged (the task is already terminal)

The two effects are idempotent on independent footings — the row on taskId+event+pr, the task on its own status — deliberately not gated on each other. If the process dies between them, a repeated event repairs the task instead of leaving a permanent inconsistency.

An originating state other than waiting-merge is recorded as (was waiting-human), so an unexpected route shows up in the timeline rather than passing silently.

D31 — renderSummary named two different things

Importing the shared library's renderSummary beside entry.mjs's local function of the same name was a SyntaxError at module load: the orchestrator would not start at all. The collision is the symptom; the names were the problem, so both are renamed:

• renderStateSummary — writes state/SUMMARY.md
• renderStepSummary — renders the Actions Step Summary (now paired with the existing writeStepSummary)

While there: the terminal-state list had been written out inline in more than one place. It is now the single exported TERMINAL_STATUSES — duplicated lists are this codebase's recurring failure mode (the missing #33 acceptance row, the lib/ vs shared/ paths, the deepseek-flash id).

Verified

Case	Result
merged → accepted	pass
closed-unmerged → rejected	pass
duplicate event: no second transition, no duplicate row	pass
origin state other than waiting-merge → transitions, records (was …)	pass
released → status untouched	pass
missing task → no throw	pass

Plus the standing suite: route decisions, CLI guards (stage whitelist, idempotent closing, claimability), and the orchestrator paths.

Related, not in scope

The R2 state layer currently holds five tasks that GitHub has already closed or merged, all stranded in waiting-human for the same underlying reason (the host had no closure path). Those are being reconciled separately by hand, since the state layer lives in R2 and only the owner can push to it. The sweep skill's blind spot — it only lists open GitHub items, so it cannot detect this whole direction — is a norms-layer change and should go through a proposal PR rather than ride along here.

[github-actions]

Coverage

Metric	%	Covered / Total
Lines	90.19%	1003/1112
Statements	89.06%	1083/1216
Functions	91.03%	193/212
Branches	76.43%	519/679