feat: scheduled agent execution via activity-core (WP-0006, v1.3.0)

Enable kaizen agents to run on a regular cadence against a preselected repo
roster, orchestrated by activity-core and prepared by kaizen-agentic — without
this repo owning cron, Temporal workers, or an LLM runtime.

CLI + module:
- src/kaizen_agentic/schedule.py — .kaizen/schedule.yml parse/validate/scaffold
- `kaizen-agentic schedule` group: init, validate, list, prepare <agent>
  (prepare bundles agent prompt + memory + metrics + repo pointers, offline)
- tests/test_schedule_cli.py — 15 tests

Contract & design:
- ADR-005 scheduled agent execution; schema doc + example manifest
- discover_kaizen_scheduled_repos resolver spec, state-hub roster fields,
  kaizen.schedule.prepared event payload, activity-core handoff checklist
- INTEGRATION_PATTERNS Pattern 2 extended with roster model

ActivityDefinition drafts (enabled: false):
- weekly-coach-orientation, weekly-optimization-review

Docs: agency-framework, CLI cheat sheet, PACKAGE_RELEASE runner prereqs,
EcosystemIntegration, CHANGELOG, TODO. Workplan closed (status: done).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/integrations/activity-core-handoff-wp0006.md

@@ -0,0 +1,69 @@
+# activity-core Handoff — Scheduled Agent Execution (WP-0006)
+
+Coordination checklist for the **activity-core** team to enable kaizen scheduled
+agent runs. kaizen-agentic owns the schedule contract, the prepare CLI, and the
+ActivityDefinition **drafts**; activity-core owns the resolver, the schedule
+firing, and task creation (repo boundary, ADR-005).
+
+Open this as an activity-core issue/PR titled *"Enable kaizen scheduled agent
+execution (WP-0006)"* and track the boxes there.
+
+## What kaizen-agentic ships (done in this repo)
+
+- [x] `.kaizen/schedule.yml` schema + `schedule validate|init|list|prepare` CLI
+- [x] ADR-005 contract
+- [x] Resolver spec: [discover-kaizen-scheduled-repos.md](discover-kaizen-scheduled-repos.md)
+- [x] State Hub roster fields design: [state-hub-roster-fields.md](state-hub-roster-fields.md)
+- [x] Draft definitions (`enabled: false`):
+      [weekly-coach-orientation](activity-definitions/weekly-coach-orientation.md),
+      [weekly-optimization-review](activity-definitions/weekly-optimization-review.md)
+- [x] Event payload spec: [kaizen-schedule-prepared-event.md](kaizen-schedule-prepared-event.md)
+
+## What activity-core must do
+
+- [ ] **Implement resolver** `discover_kaizen_scheduled_repos` per the spec
+      (hub roster ∩ repos with valid `.kaizen/schedule.yml`).
+- [ ] **Add resolver unit tests** using the four fixtures in the spec.
+- [ ] **Copy definitions** from `docs/integrations/activity-definitions/`
+      (`weekly-coach-orientation.md`, `weekly-optimization-review.md`) into the
+      activity-core catalog path (per ACT-ADR-002).
+- [ ] **Register** each definition slug in the activity-core index.
+- [ ] **Run** `make sync-activity-definitions` in activity-core.
+- [ ] **Wire cron** triggers (Mon 09:00 / 10:00 Europe/Berlin) to the resolver.
+- [ ] **Smoke test** against a pilot repo (see below) with the definition still
+      `enabled: false` (dry-run task creation).
+- [ ] **Enable gradually** — flip one definition to `enabled: true` in staging
+      after the smoke test passes.
+- [ ] **Verify runner prerequisites** — `kaizen-agentic` on PATH and the Gitea
+      PyPI extra index if the runner installs from registry (see
+      [PACKAGE_RELEASE.md](../PACKAGE_RELEASE.md)).
+
+## State Hub team (the-custodian)
+
+- [ ] Optional: add `kaizen_schedule_enabled` repo flag + `GET /repos/` filter
+      (v2 pre-filter; the repo file remains the source of truth).
+
+## Smoke test (manual, runner-agnostic)
+
+```bash
+cd /path/to/pilot-repo
+kaizen-agentic schedule init            # if not already present
+kaizen-agentic schedule validate        # exit 0
+kaizen-agentic schedule list            # shows coach + optimization enabled
+kaizen-agentic schedule prepare coach   # non-empty orientation bundle
+```
+
+Then in activity-core: run the resolver (dry-run) and confirm one
+`scheduled_run` per enabled `(repo, agent)` with a correct `prepare_command`.
+
+## Pilot roster
+
+- `kaizen-agentic` (dogfood)
+- `the-custodian` (hub operator)
+- one additional custodian-domain repo with `.kaizen/` state (TBD at pilot time)
+
+## Related
+
+- [ADR-005](../adr/ADR-005-scheduled-agent-execution.md)
+- [INTEGRATION_PATTERNS.md Pattern 2](../INTEGRATION_PATTERNS.md)
+- [KAIZEN-WP-0006](../../workplans/kaizen-agentic-WP-0006-scheduled-agent-execution.md)