feat: prepare-new-server playbook + role struktura

playbook prepare-new-server.yml:
- update systemu
- deploy user (UID 1000, heslo zamknuto)
- SSH klic pro deploy uzivatele
- adresarova struktura (/home/deploy/{docker,scripts,backups,logs,...})
- Docker Engine + Compose plugin (bez sudo)
- UFW firewall (22, 80, 443)
- fail2ban
- overeni docker bez sudo

Role (kazda v samostatnem adresari):
- common: update, base packages, timezone
- deploy-user: vytvoreni usera UID 1000
- ssh-keys: authorized_keys deployment
- firewall: UFW konfigurace
- docker: Docker Engine + Compose + daemon.json
- directories: /home/deploy/{docker/<sluzba>,backups,scripts,logs}

Pouziti:
  ansible-playbook -i inventory.yml playbooks/prepare-new-server.yml

roles/ssh-keys/tasks/main.yml

@@ -0,0 +1,23 @@
+---
+- name: Over ze deploy_ssh_public_keys je nastaveno
+  ansible.builtin.assert:
+    that:
+      - deploy_ssh_public_keys is defined
+      - deploy_ssh_public_keys | length > 0
+    fail_msg: "deploy_ssh_public_keys neni nastaven. Pridej ho do group_vars/all.yml nebo inventory."
+
+- name: Nastav authorized_keys pro deploy uzivatele
+  ansible.posix.authorized_key:
+    user: "{{ deploy_user }}"
+    state: present
+    key: "{{ item }}"
+    exclusive: false  # neprepisuj existujici klice
+  loop: "{{ deploy_ssh_public_keys }}"
+  when: deploy_ssh_public_keys | length > 0
+
+- name: Nastav spravna opravneni na authorized_keys
+  ansible.builtin.file:
+    path: "{{ ssh_key_path }}"
+    owner: "{{ ssh_key_owner }}"
+    group: "{{ ssh_key_group }}"
+    mode: "{{ ssh_key_mode }}"