feat(ms-ai-architect): Sesjon 24 — C1 Tier 2 lokal launchd-scheduler (deteksjon-only, ToS-trygt) [skip-docs]

Tier 1 (SessionStart-hook) kjører deteksjon kun når en Claude-sesjon starter.
Tier 2 installerer en lokal launchd LaunchAgent som fyrer SAMME Claude-frie
entrypoint daglig (kl. 03:00), uavhengig av sesjoner = ekte bakgrunn mellom
sesjoner. ToS-trygt: entrypointet kan strukturelt ikke invokere claude.

Søk-først-verifisert (2026-06): launchd > cron (Apple-anbefalt; cron krever
Full Disk Access); StartCalendarInterval fanger opp etter dvale; launchd har
minimalt PATH + ekspanderer ikke ~; process.execPath = Cellar-sti som dør ved
`brew upgrade node` → plistens PATH inkluderer /usr/local/bin.

Levert (TDD, test FØR kode):
- lib/launchd-plist.mjs (REN, SKRIVER ALDRI): renderPlist (XML-escape,
  StartCalendarInterval, PATH-fix), defaultLabel, resolvePaths.
- scheduler.mjs (TYNN CLI): install|uninstall|status|run-now|print|run.
  Strukturelt Claude-fri (kun process.execPath på run-detection.mjs +
  launchctl; kilde-grep-testet). run gater på os_scheduler_cadence →
  delegerer til run-detection.mjs. uid-0-nekt; idempotent bootout.
- detection-schedule.mjs (additiv, Tier-1 urørt): os_scheduler_cadence
  ('daily' default | 'interval') + daysSinceLastPoll ren helper.
- commands/kb-update.md: Tier-1/Tier-2-doc + caveats (uninstall=pause;
  re-install etter node-upgrade).

Operatør-valg: daglig default, kadens egen innstilling (settes i onboarding/C2).

Verifisert: launchd-plist 13/13 · detection-schedule 21/21 · kb-update 173 ·
kb-eval 100 · validate 239/0 · test-hooks 6/6 · plutil -lint OK · live
install→status→idempotent→uninstall på maskinen (gui/501, rent).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/kb-update/lib/detection-schedule.mjs

@@ -19,6 +19,11 @@ export const DEFAULT_SCHEDULE_CONFIG = Object.freeze({
   enabled: false,
   interval_days: 7,
   include_skill_lifecycle: true,
+  // Tier 2 (launchd) cadence. 'daily' = poll on every (daily) fire; 'interval'
+  // = throttle to interval_days via the same staleness gate Tier 1 uses. Read
+  // ONLY by the Tier-2 entrypoint (scheduler.mjs run); the Tier-1 hook ignores
+  // it, so existing behavior is unchanged. Operator default: daily.
+  os_scheduler_cadence: 'daily',
 });
 
 // The ordered, Claude-FREE detection pipeline. Every step is a local node
@@ -45,6 +50,10 @@ function coerce(key, raw) {
     const n = Number.parseInt(v, 10);
     return Number.isFinite(n) && n > 0 ? n : undefined;
   }
+  if (key === 'os_scheduler_cadence') {
+    // Only 'interval' opts out of daily; any other/garbage value => default daily.
+    return v === 'interval' ? 'interval' : 'daily';
+  }
   return undefined;
 }
 
@@ -112,6 +121,22 @@ export function shouldRunDetection(config, lastPollDaysAgo, opts = {}) {
   return { run: false, reason: 'fresh (within interval)' };
 }
 
+/**
+ * Days since the last sitemap poll, read from a parsed change-report.json.
+ * Pure; mirrors the SessionStart hook's computation. Missing/invalid
+ * last_poll => Infinity ("infinitely stale" => the 'interval' cadence runs).
+ * @param {object|null} report  parsed change-report.json ({ last_poll?: string })
+ * @param {number} now  Date.now()
+ * @returns {number}
+ */
+export function daysSinceLastPoll(report, now) {
+  const DAY_MS = 24 * 60 * 60 * 1000;
+  if (!report || !report.last_poll) return Infinity;
+  const t = new Date(report.last_poll).getTime();
+  if (!Number.isFinite(t)) return Infinity;
+  return (now - t) / DAY_MS;
+}
+
 /**
  * Build a compact one-liner summarizing skill-lifecycle signals for the
  * SessionStart hook. Pure; tolerant of partial/missing reports. Returns null