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/lifecycle-activate-node.md

@@ -0,0 +1,36 @@
+---
+name: lifecycle-activate-node
+risk_class: config_mutation
+inputs: [node_name]
+verification: "homelab service <name> health (if it hosts a service); homelab doctor (if it's a client)"
+docs_update_checklist: [doc_page_complete]
+transition: "provisioning -> active"
+---
+
+# Lifecycle: activate a node
+
+Per [oikos/ontology.yaml](../oikos/ontology.yaml). Requires: age key
+enrolled if it needs secrets, mesh joined if it needs off-LAN reach,
+ingress live if public, health check answering, doc page complete,
+ledger entry.
+
+1. If the node is a `homelab` client: finish enrollment per
+   [client-enrollment.md](client-enrollment.md) (`--finalize-pubkey`,
+   mesh join, `homelab doctor` green).
+2. If it hosts a public service: add the `services:` entry in
+   `inventory.yaml` (backend, url, doc_page, config_repo, risk_notes —
+   see the Week-1 service contract fields) and wire the Caddy route in
+   `dtoro/caddy-conf`.
+3. Confirm the health check answers: `homelab service <name> health` or
+   a direct `curl`.
+4. Flip `state: provisioning` → `state: active` (or delete the `state:`
+   field — `active` is the default) in `inventory.yaml`.
+5. Complete the doc page (stub → full narrative: role, specs, how it's
+   configured, dependencies).
+6. Record the activation: `oikos/ledger.py append host:<name> activate
+   config_mutation --result ok` (or let the CLI wrapper do this once
+   Week 3's runbook automation lands).
+
+Regenerate derived data: `python3 mcp/build_host_files.py && python3
+oikos/gen-topology.py` so `hosts/<name>.yaml`, the topology diagram, and
+the context card all reflect the new state.