nixos: remove taffybar ecosystem follows and fix bitwarden rename

Remove top-level gtk-sni-tray, gtk-strut, status-notifier-item,
dbus-menu, and dbus-hslogger inputs that only existed as follows
targets. Let taffybar and imalison-taffybar resolve their own
ecosystem deps, eliminating cascading lock update headaches.

Also rename bitwarden -> bitwarden-desktop in kat.nix (nixpkgs rename).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dotfiles/config/taffybar/flake.lock

@@ -480,8 +480,8 @@
         "xmonad-contrib": "xmonad-contrib"
       },
       "locked": {
-        "lastModified": 1770862040,
-        "narHash": "sha256-pWu+hd/AExuWluAU6DLlV1Gljj7rIr/V+ecXsTmnw04=",
+        "lastModified": 1770908792,
+        "narHash": "sha256-E7V1tC2BfyWKW4HRw/OmkZyvTFxG4JDVHXUCo0cntzo=",
         "path": "/home/imalison/dotfiles/dotfiles/config/taffybar/taffybar",
         "type": "path"
       },