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

.gitignore

@@ -0,0 +1,38 @@
+# Terraform
+*.tfstate
+*.tfstate.*
+*.tfstate.backup
+.terraform/
+.terraform.lock.hcl
+terraform.tfvars
+crash.log
+override.tf
+override.tf.json
+*_override.tf
+*_override.tf.json
+
+# Ansible
+ansible/inventory.ini
+ansible/*.retry
+.ansible/
+
+# Outputs
+outputs/
+*.pem
+*.key
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Secrets
+*.tfvars
+secrets/
+.env