Initial import: phase docs, configs, Claude conventions

Phase 1-3 runbooks and design notes, version pins, config templates,
project-history conventions, cluster-inspector read-only credentials setup.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

configs/image-builder/proxmox-lab.json.example

@@ -0,0 +1,8 @@
+{
+  "disk_format": "raw",
+  "kubernetes_semver": "v1.35.9",
+  "kubernetes_series": "v1.35",
+  "kubernetes_deb_version": "1.35.9-1.1",
+  "iso_file": "local:iso/ubuntu-24.04.4-live-server-amd64.iso",
+  "iso_url": ""
+}