Full lab documentation and infrastructure as code

- Trino catalogs, Grafana, Spark jobs, LDAP LDIF, NPM compose
- Airflow DAG scripts, Proxmox VM inventory, network docs
- Ansible playbook, Gitea CI validate workflow
- Backup and health-check scripts, cron documentation
- Homepage DOCS tab with links to all documentation
- Extended collect-fleet-config.sh and populate-repo.py

ansible/README.md

@@ -0,0 +1,9 @@
+# Ansible — ATC Lakehouse
+
+```bash
+# From atc-docker01 (with ansible installed)
+cd /root/lakehouse/ansible
+ansible-playbook -i inventory.ini playbook.yml
+```
+
+Requires SSH mesh (`/root/.ssh/atc_cluster`) on all targets.