Oikos Week 1: kernel policy, ontology, service contract, topology gen

Adds the Oikos agent-OS kernel: oikos/policy.yaml (risk classes +
approval rules for every homelab/MCP command), oikos/ontology.yaml
(8-domain systems model, typed relationships, node lifecycle), and
OIKOS.md (OODA loop operating brief, linked from AGENTS.md).

Extends inventory.yaml with a stable service contract (doc_page,
config_repo, risk_notes) on all 17 services, and a structured
archaeology: section for the 13 destroyed LXCs (was scattered
comments + a narrative table). Fixes stale drift found in the
process: authentik's backend pointed at a retired LXC (124); core
has run on the VPS since 2026-05-31.

Adds oikos/gen-topology.py, generating infrastructure/topology.md
(Mermaid compute/ingress + storage views) from inventory.yaml.
build_host_files.py now carries state/storage/depends_on into
generated hosts/*.yaml.

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

hosts/gitea.yaml

@@ -5,6 +5,7 @@ name: gitea
 kind: lxc
 os: linux
 role: git-server
+state: active
 host: hubris
 pve_id: 104
 lan_ip: 192.168.8.121
@@ -26,6 +27,9 @@ services_hosted:
   url: https://git.hubris.network
   backend: gitea
   backend_url: http://192.168.8.121:3000
+  doc_page: containers/104-gitea.md
+  config_repo: dtoro/gitea-customizations
+  risk_notes: hosts all config repos + deploy webhooks; outage blocks auto-deploy and sync
 notes:
 - Bare repos live at /mnt/library/repos/dtoro/*.git
 see_also: