port build_host_files.py to Go, simplify Hermes MCP, cutover final

- cmd/hermes/main.go: removed redundant /mcp endpoint — Hermes gateway now
  serves only /query + /healthz. MCP goes direct to API (:8090/mcp).
- cmd/oikos/build_hosts.go: Go port of mcp/build_host_files.py as
  'oikos build-hosts'. Reads inventory.yaml, writes hosts/*.yaml.
- cmd/oikos/main.go: added build-hosts role.
- docker-compose.yml: hermes service simplified.
- apps/105: all 6 Oikos services stopped + disabled (confirmed inactive).
- Watchdog cron installed, API stop/restart verified.
- Infisical bootstrap pending (image pull timeout — retry separately).

Remaining:
- Port bin/homelab CLI to Go (separate plan — large surface)
- Caddy DNS push (needs dtoro/caddy-conf repo access)
- Rollback drill

hosts/haos.yaml

@@ -1,27 +1,27 @@
-# Generated by mcp/build_host_files.py from inventory.yaml.
-# Do NOT edit by hand — your changes will be overwritten.
-# Source of truth: ../inventory.yaml
-name: haos
-kind: vm
-os: linux
-role: home-automation
-state: active
+# Generated by oikos build-hosts from inventory.yaml.
+# Do NOT edit by hand.
+
 host: hubris
-pve_id: 108
+kind: vm
 lan_ip: 192.168.8.101
+mcp_endpoint: https://mcp.hubris.network/mcp
 mesh:
   tailscale:
     fqdn: homeassistant
 mesh_globals:
-  primary: netbird
   accepted:
-  - netbird
-  - tailscale
+    - netbird
+    - tailscale
+  primary: netbird
+name: haos
+os: linux
+pve_id: 108
+role: home-automation
 runs:
-- haos
-services_hosted:
-- name: haos
-  backend: haos
-  doc_page: knowledge/wiki/vms/108-haos.md
-mcp_endpoint: https://mcp.hubris.network/mcp
+  - haos
 secrets_issuance_endpoint: https://secrets.hubris.network/issue
+services_hosted:
+  - backend: haos
+    doc_page: knowledge/wiki/vms/108-haos.md
+    name: haos
+state: active