Oikos Week 2: Service Console v0, change ledger, node relations, runbooks

Adds the shared kernel modules (oikos/policy.py, oikos/relations.py,
oikos/ledger.py) that let every surface — CLI, MCP, context-card
generator — agree on risk classification and ontology graph walks
from one implementation.

homelab CLI: `service <name> explain|health|docs|log|actions|history`
(Service Console v0), `change preflight <service>`, `node <name>
relations`. Restart and client add/remove now append change-ledger
entries (ledger/*.jsonl, committed alongside the change they record).

mcp/server.py mirrors explain/preflight/get_relations/get_change_history
as MCP tools, card-first so agent orientation is one call instead of
several search_docs/get_page round-trips.

oikos/gen-topology.py now also emits a compact context card per host
and service (oikos/cards/*.md) — identity, blast radius, safe actions +
risk class, doc pointer, recent ledger history.

runbooks/*.md: service health check, config change + deploy, client
enrollment, incident investigation, and the five node lifecycle
transitions (provision/activate/migrate/deprecate/destroy), each with
machine-readable frontmatter (risk class, inputs, verification,
docs-update checklist). Wired into HERMES.md so agents load these
instead of rediscovering topology per-task.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

runbooks/client-enrollment.md

@@ -0,0 +1,35 @@
+---
+name: client-enrollment
+risk_class: config_mutation
+inputs: [hostname, kind, role]
+verification: "homelab doctor (on the new client)"
+docs_update_checklist: [hosts_narrative_page_if_lxc_or_vm]
+---
+
+# Client enrollment
+
+Goal: bring a new host (workstation, LXC, VM) into the mesh, inventory,
+and secrets model. This wraps the existing `homelab client add` flow —
+see [operations/agent-enrollment.md](../operations/agent-enrollment.md)
+for the full walkthrough; this runbook is the risk/lifecycle framing.
+
+1. On any enrolled client: `homelab client add <hostname>` — appends a
+   `hosts.<name>:` block to `inventory.yaml` (lifecycle `state: planned`
+   → `provisioning`, per [oikos/ontology.yaml](../oikos/ontology.yaml)),
+   commits + pushes.
+2. Join the new host to Netbird (out-of-band, console or setup key).
+3. On the new host: run `bootstrap.sh` (add `--with-hermes` to also
+   enroll the Hermes agent). This provisions `/etc/age/key.txt`, the
+   sync timer, and prints an age pubkey.
+4. Back on an enrolled client: `homelab client add <hostname>
+   --finalize-pubkey <age1...>` — sets `age_pubkey`, grants shared
+   secrets, re-keys SOPS, commits + pushes. This is the
+   `provisioning → active` transition.
+5. Verify: `homelab doctor` on the new client should show all checks
+   green (clone, sync timer, age key, CLI symlink, MCP reachable).
+
+Docs-update checklist: if the new host is an LXC/VM, add its narrative
+page under `containers/` or `vms/` and set `doc_page` in its inventory
+entry (host-level cards don't have a `doc_page` field yet — services do;
+narrative pages are still found via the generated `see_also` in
+`hosts/<name>.yaml`).