playbook: Add fstrim timer role

playbook/roles/fstrim/meta/main.yml

+---
+dependencies:
+  - role: package
+    package_name: util-linux
+    package_state: present

playbook/roles/fstrim/tasks/main.yml

+---
+- name: Check if fstrim command exists
+  stat:
+    path: /sbin/fstrim
+  register: fstrim
+
+- name: Install systemd files
+  template:
+    src: '{{ item }}'
+    dest: '/etc/systemd/system/'
+    owner: root
+    group: root
+    mode: 0644
+  with_items:
+    - fstrim.service
+    - fstrim.timer
+  when: fstrim.stat.exists
+
+- name: Enable fstrim timer
+  service:
+    name: fstrim.timer
+    enabled: true
+  when: fstrim.stat.exists

playbook/roles/fstrim/templates/fstrim.service

+[Unit]
+Description=Discard unused blocks
+
+[Service]
+Type=oneshot
+ExecStart=/sbin/fstrim -a

playbook/roles/fstrim/templates/fstrim.timer

+[Unit]
+Description=Discard unused blocks once a week
+Documentation=man:fstrim
+
+[Timer]
+OnCalendar=weekly
+AccuracySec=1h
+Persistent=true
+
+[Install]
+WantedBy=multi-user.target