fedora-intune: cron for Intune config scripts, Defender remediation script

Himmelblau installs Intune Linux custom configuration scripts as
/etc/cron.d jobs, and the image had no cron, so a script policy failed to
apply. Add cronie and enable crond.

Add a custom configuration script that repairs Microsoft Defender on its
schedule: finishes first-boot setup, restarts a stopped daemon, onboards with
the tenant's mdatp_onboard.json (pasted into the script in Intune), and
re-enables real-time protection and updates definitions when needed.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

images/fedora-intune/files/50-himmelblau.preset

@@ -2,3 +2,5 @@
 enable himmelblaud.service
 enable himmelblaud-tasks.service
 enable himmelblau-hsm-pin-init.service
+# Runs the Intune custom configuration scripts Himmelblau puts in /etc/cron.d.
+enable crond.service