Add `labctl provision register` to re-add machines to installed state
without reprovisioning (e.g. after bastion state loss). Full stack:
protocol type, bastion API + WS handler, labd route, CLI command.
Add `labctl app k3s kubeconfig <target>` to fetch kubeconfig from a
k3s node via SSH, rewrite server URL, and merge into ~/.kube/config.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>