Add Niri desktop configuration with integrated utilities

- Introduced a new power menu script using fuzzel for session management.
- Updated Bellerophon configuration to include Niri desktop and its components.
- Removed obsolete README for Niri and consolidated its configuration files.
- Added swayidle and swaylock integration for idle management and screen locking.
- Implemented waybar for status bar functionality with basic configuration.
- Created fuzzel integration for application launching and menu access.
- Added zenbook debugging scripts for display and keyboard diagnostics.
- Migrated keyring and other configurations to streamline Niri setup.
- Enhanced display management with systemd services for better integration.

hosts/common/optional/niri/fuzzel.nix

@@ -0,0 +1,8 @@
+{pkgs, ...}: {
+  environment.systemPackages = with pkgs; [fuzzel];
+
+  # Provide a simple system-wide wrapper script in /etc/profile.d or /etc to make fuzzel available
+  environment.etc."profile.d/fuzzel.sh".text = ''
+    export PATH="${pkgs.fuzzel}/bin:$PATH"
+  '';
+}