docs: concept annexation, provider/reference docs, ACT-1 groundwork

Mosaic concepts pages now own the adapted content; source/license
metadata under docs/reference/concepts. Adds ACT-1 agent-context
planning capture, pinned concept test package + preparation utility,
foundation observation notes (durability, evidence, federation,
onboarding, workflow), and the #1495 consolidation assessment.
TOOLS.md updated for the host-dev launcher.

docs/reference/templates/HEARTBEAT.md

@@ -0,0 +1,28 @@
+---
+summary: "Migration guide for the retired HEARTBEAT.md workspace file"
+title: "Retired HEARTBEAT.md workspace file"
+read_when:
+  - Migrating an older workspace that still has HEARTBEAT.md
+---
+
+# HEARTBEAT.md is retired
+
+OpenClaw no longer creates `HEARTBEAT.md` in new workspaces or reads it at runtime. Heartbeat instructions now live in the system-owned monitor scratch in the shared state database.
+
+Manage the current monitor scratch with the monitor job id from `openclaw automations list --all`:
+
+```bash
+openclaw automations scratch <jobId>
+openclaw automations scratch <jobId> --set "..."
+openclaw automations scratch <jobId> --file notes.md
+openclaw automations scratch <jobId> --unset
+```
+
+If an older workspace still contains `HEARTBEAT.md`, run `openclaw doctor --fix`. Doctor imports its instructions into monitor scratch, converts valid legacy `tasks:` entries into cron jobs, archives the original under the state directory, and removes the workspace file.
+
+## Related
+
+- [Heartbeat](/gateway/heartbeat)
+- [Cron CLI](/cli/cron)
+- [Doctor](/cli/doctor)
+- [Heartbeat config](/gateway/config-agents)