Add ZFS support to sleeper-service

- Replace ext4 with ZFS pool 'filepool' for enhanced data integrity
- Add ZFS auto-scrub and TRIM services for file server
- Configure proper ZFS datasets: root, nix, var, storage
- Add networking hostId (a1b2c3d4) required for ZFS
- Update NFS and Transmission to use ZFS mount points
- Change file ownership to 'sma' user for server configuration
- Add comprehensive ZFS setup documentation

Ready for deployment with proper file server storage backend.

modules/network/network-sleeper-service.nix

@@ -10,6 +10,7 @@
   # Machine-specific network configuration
   networking = {
     hostName = "sleeper-service";
+    hostId = "a1b2c3d4";  # Required for ZFS support
     
     # Enable systemd-networkd for static networking
     useNetworkd = true;