Add overlay filesystem support and update zinit configuration

- Added overlay.ko module installation for container support in install-firmware-minimal.sh
- Added udevmon service for hardware event monitoring
- Updated udev-trigger dependency to include udevmon
- Added placeholder configurations for mycelium and shm services

configs/zinit/udev-trigger.yaml

@@ -1,4 +1,5 @@
 exec: sh /etc/zinit/init/udev.sh
 oneshot: true
 after:
+  - udevmon
   - udevd