fix: configure explicit NTP servers in timesyncd instead of relying on DHCP

Gateway at 192.168.20.1 was being provided via DHCP as the NTP server but
does not serve NTP, causing NodeClockNotSynchronising across all nodes.

roles/common/handlers/main.yaml

@@ -4,3 +4,9 @@
     name: sshd
     state: restarted
   become: true
+
+- name: Restart timesyncd
+  ansible.builtin.systemd:
+    name: systemd-timesyncd
+    state: restarted
+  become: true

roles/common/tasks/time.yaml

@@ -10,6 +10,14 @@
     name: "{{ timezone }}"
   when: ansible_user_id == "root"
 
+- name: Configure NTP servers for systemd-timesyncd
+  ansible.builtin.lineinfile:
+    path: /etc/systemd/timesyncd.conf
+    regexp: "^#?NTP="
+    line: "NTP=0.debian.pool.ntp.org 1.debian.pool.ntp.org 2.debian.pool.ntp.org 3.debian.pool.ntp.org"
+  become: true
+  notify: Restart timesyncd
+
 - name: Enable and start systemd-timesyncd
   ansible.builtin.systemd:
     name: systemd-timesyncd