feat: Add HA Kubernetes cluster with Terraform + Ansible

- 3x CX23 control plane nodes (HA)
- 4x CX33 worker nodes
- k3s with embedded etcd
- Hetzner CCM for load balancers
- Gitea CI/CD workflows
- Backblaze B2 for Terraform state

ansible/inventory.tmpl

@@ -0,0 +1,18 @@
+[control_plane]
+{% for ip in control_plane_ips %}
+{{ ip }}
+{% endfor %}
+
+[workers]
+{% for ip in worker_ips %}
+{{ ip }}
+{% endfor %}
+
+[cluster:children]
+control_plane
+workers
+
+[cluster:vars]
+ansible_user=root
+ansible_python_interpreter=/usr/bin/python3
+k3s_version=latest