Harden against bot floods and add post-provisioning service check

- Traefik rate-limits all routes (60 req/min standard, 300 for Nextcloud)
  and writes access logs to /var/log/traefik/access.log
- Fail2ban watches Traefik access logs and bans IPs after 10 x 403/404
  within 60 s for 24 h
- Nextcloud html directory created as www-data (UID 33) so Apache can
  process .htaccess and serve requests correctly
- scripts/check-services.sh verifies all seven endpoints return the
  expected HTTP status after provisioning

ansible/roles/base/tasks/main.yml

@@ -126,6 +126,26 @@
 
 # --- Fail2ban ---
 
+- name: Deploy fail2ban filter for Traefik
+  ansible.builtin.copy:
+    src: filter.d/traefik.conf
+    dest: /etc/fail2ban/filter.d/traefik.conf
+    owner: root
+    group: root
+    mode: "0644"
+  notify: Restart fail2ban
+  tags: base
+
+- name: Deploy fail2ban jail for Traefik
+  ansible.builtin.copy:
+    src: jail.d/traefik.conf
+    dest: /etc/fail2ban/jail.d/traefik.conf
+    owner: root
+    group: root
+    mode: "0644"
+  notify: Restart fail2ban
+  tags: base
+
 - name: Enable and start fail2ban
   ansible.builtin.service:
     name: fail2ban