Roadmap: Add Nextcloud MariaDB 10.5->10.6 upgrade task

compose_files/INFRASTRUCTURE_ROADMAP.md

@@ -20,6 +20,19 @@ This roadmap addresses critical issues, security vulnerabilities, and operationa
 
 ### Tasks
 
+- [ ] **Upgrade Nextcloud MariaDB 10.5 → 10.6**
+  - File: `nextcloud.yml`
+  - Current: `mariadb:10.5` (2.2GB database)
+  - Target: `mariadb:10.6` (recommended by Nextcloud 30)
+  - Steps:
+    1. Backup: `docker exec compose_files_db_1 mariadb-dump -uroot -p'eccmts42*' --all-databases > /home/icke/backups/nextcloud_mariadb_before_10.6_$(date +%Y%m%d).sql`
+    2. Stop: `cd /home/icke/compose_files && docker-compose -f nextcloud.yml down`
+    3. Edit: Change `image: mariadb:10.5` → `image: mariadb:10.6`
+    4. Start: `docker-compose -f nextcloud.yml up -d`
+    5. Upgrade: `docker exec compose_files_db_1 mariadb-upgrade -uroot -p'eccmts42*'`
+  - Impact: Better performance, Nextcloud 30 compatibility
+  - Downtime: ~5 minutes
+
 - [ ] **Change N8N password** from "changeme" to secure password
   - File: `n8n.yml`
   - Impact: Critical security fix