feat: complete LOOP-WP-0003 and LOOP-WP-0004

Registry hygiene: 3-round pilot bootstrap smoke, helix_forge rollout
expansion, daily cadence promotion (DEC-006). Loop regulator: daily
collector and weekly session cadence (DEC-007), rotation runbook (T09).

docs/decisions/DEC-006-registry-hygiene-cadence-promotion.md

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+# DEC-006 — Registry Hygiene Cadence Promotion
+
+**Status:** accepted
+**Date:** 2026-06-18
+**Owner:** Bernd (Coulomb operator)
+**Workplan:** LOOP-WP-0003 T07
+
+---
+
+## Decision
+
+Promote **registry-hygiene** from `bootstrap` (hourly) to `stabilize` (daily 07:00 Europe/Berlin).
+
+## Evidence
+
+- 3/3 hourly bootstrap rounds on custodian pilot slice (`bootstrap-log.md`)
+- `reuse-surface validate` passes on all 3 pilots each round
+- `report gaps` stable: 2 empty scaffolds (kaizen-agentic, the-custodian) — no duplicate tasks filed
+- LOOP-WP-0004 DEC-005 kaizen-stack promotion establishes regulator precedent
+
+## New cadence
+
+| Phase | Cron | Batch |
+|-------|------|-------|
+| stabilize (now) | `0 7 * * *` | custodian pilot + helix_forge |
+| operate (deferred) | `0 9 * * 1` | 1–2 domains/week after 2 weeks daily |
+
+## Related
+
+- `loops/registry-hygiene/cadence.yml`
+- `activity-definitions/hourly-registry-hygiene-sweep.md` (cron updated to daily)