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/roles/common/tasks/main.yml

@@ -0,0 +1,58 @@
+---
+- name: Update apt cache
+  apt:
+    update_cache: true
+    cache_valid_time: 3600
+
+- name: Upgrade packages
+  apt:
+    upgrade: dist
+  when: common_upgrade_packages | default(false)
+
+- name: Install required packages
+  apt:
+    name:
+      - apt-transport-https
+      - ca-certificates
+      - curl
+      - gnupg
+      - lsb-release
+      - software-properties-common
+      - jq
+      - htop
+      - vim
+    state: present
+
+- name: Disable swap
+  command: swapoff -a
+  changed_when: true
+
+- name: Remove swap from fstab
+  mount:
+    name: swap
+    fstype: swap
+    state: absent
+
+- name: Load br_netfilter module
+  modprobe:
+    name: br_netfilter
+    state: present
+
+- name: Persist br_netfilter module
+  copy:
+    dest: /etc/modules-load.d/k8s.conf
+    content: |
+      br_netfilter
+      overlay
+    mode: "0644"
+
+- name: Configure sysctl for Kubernetes
+  sysctl:
+    name: "{{ item.name }}"
+    value: "{{ item.value }}"
+    state: present
+    reload: true
+  loop:
+    - { name: net.bridge.bridge-nf-call-iptables, value: 1 }
+    - { name: net.bridge.bridge-nf-call-ip6tables, value: 1 }
+    - { name: net.ipv4.ip_forward, value: 1 }