feat: add gortium.clamav NixOS module

- New module at modules/nixos/services/clamav.nix
- Options: enable (CLI-only), enableDaemon (full services),
  onAccessScanning (clamonacc), scanPaths, dailyScanTime
- All scans are logging-only — no auto-quarantine or deletion
- uConsole: CLI tools only (enableDaemon=false)
- lazyworkhorse: full setup with on-access scanning, daily 3 AM scan

Also: remove neovim from uConsole (fails cross-compile, emacs available)

hosts/uconsole-cm5/configuration.nix

@@ -83,7 +83,6 @@
     fd
     htop
     tmux
-    neovim
 
     # ===== HAM Radio =====
     wsjtx
@@ -202,10 +201,9 @@
   # ============================================================
   # ClamAV antivirus — daily automatic scans
   # ============================================================
-  services.clamav = {
-    daemon.enable = true;
-    updater.enable = true;
-    scanner.enable = true;
+  gortium.clamav = {
+    enable = true;
+    enableDaemon = false;
   };
 
 }