Add daily TODO.md stale review automation (CUST-WP-0056)

Schedule 08:30 Berlin daily scan for TODO.md unchanged 6+ days;
emit review tasks and promote durable work to workplans.

workplans/CUST-WP-0056-daily-todo-md-stale-review.md

@@ -0,0 +1,56 @@
+---
+id: CUST-WP-0056
+type: workplan
+title: "Daily TODO.md Stale Review via activity-core"
+domain: custodian
+repo: the-custodian
+status: finished
+owner: codex
+topic_slug: custodian
+created: "2026-07-08"
+updated: "2026-07-08"
+---
+
+# CUST-WP-0056 — Daily TODO.md Stale Review via activity-core
+
+## Goal
+
+Automate daily review of workstation `TODO.md` files that have not changed in
+6+ days. TODO.md is a pragmatic interruption buffer; stale files should be
+reviewed and durable items promoted to workplans (ADR-001).
+
+## State Hub scan endpoint
+
+```task
+id: CUST-WP-0056-T01
+status: done
+priority: high
+```
+
+- `GET /repos/todo-md-staleness?stale_days=6` on State Hub
+- Scans active registered repos with accessible `local_path`
+- Returns repos whose `TODO.md` mtime is older than the threshold
+
+## activity-core resolver and schedule
+
+```task
+id: CUST-WP-0056-T02
+status: done
+priority: high
+```
+
+- Resolver query `todo_md_staleness` in activity-core `state_hub.py`
+- ActivityDefinition `daily-todo-md-stale-review.md` — cron `30 8 * * *` Berlin
+- Emits one review task per stale repo; progress event `todo_md_stale_review`
+
+## Retire STATUS.md pattern
+
+```task
+id: CUST-WP-0056-T03
+status: done
+priority: medium
+```
+
+- Confirmed no `STATE.md` files across workstation repos
+- Removed erroneous `STATUS.md` from net-kingdom; `SCOPE.md` remains canonical
+- README orientation points to SCOPE.md only