Fix Nextcloud DNS resolution and implement systemd cron for background jobs

- Enable IP forwarding in security playbook (net.ipv4.ip_forward = 1)
- Add podman network firewall rules to fix container DNS/HTTPS access
- Implement systemd timer for reliable Nextcloud background job execution
- Add database optimization tasks (indices, bigint conversion, mimetypes)
- Configure maintenance window (04:00 UTC) and phone region (NO)
- Add security headers (X-Robots-Tag, X-Permitted-Cross-Domain-Policies)
- Create Nextcloud removal playbook for clean uninstall
- Fix nftables interface matching (podman0 vs podman+)

Root cause: nftables FORWARD chain blocked container egress traffic
Solution: Explicit firewall rules for podman0 bridge interface

roles/nextcloud/tasks/main.yml

@@ -138,6 +138,21 @@
   notify: restart nextcloud
   tags: [config, redis]
 
+- name: Truncate nextcloud.log to prevent bloat
+  shell: |
+    podman exec nextcloud truncate -s 0 /var/www/html/data/nextcloud.log || true
+  changed_when: false
+  failed_when: false
+  tags: [maintenance, cleanup]
+
+- name: Configure background jobs (cron)
+  include_tasks: cron.yml
+  tags: [cron, background-jobs]
+
+- name: Optimize database and apply configuration
+  include_tasks: optimization.yml
+  tags: [optimization, database]
+
 - name: Display Nextcloud deployment status
   debug:
     msg: |