cleanup: fix all stale references across .agents/ docs

- Rewrite AGENTS.md: DB as source of truth, MCP knowledge tools, archive refs
- Fix OIKOS.md: seeds/ paths, remove Python-era notes, update deployment status
- Fix commands.md, agent-enrollment.md: archive/knowledge/ links
- Fix all SKILL.md files: remove hosts/*.yaml refs, point to inventory.yaml
- Fix HERMES.md, schema.md, page-templates.md, llm-wiki.md: update paths
- Fix bootstrap.sh: identity check reads inventory.yaml
- Fix README.md, cutover-checklist.md: stale wiki references
- Move convert-wiki.py to archive/ (one-shot done)

bootstrap.sh

@@ -18,7 +18,7 @@
 #   - OS is Linux or macOS
 #   - git, age, sops are installed
 #   - at least one mesh (netbird OR tailscale) is connected
-#   - this host has an `hosts/<hostname>.yaml` entry in the repo (or refuses)
+#   - this host has an `inventory.yaml` entry in the repo (or refuses)
 
 set -euo pipefail