feat(system): comprehensive branding, styling, and system feature update

- Relocate themes to assets/themes/ and update all references.
- Implement custom SDDM theme and Plymouth theme enhancements.
- Add themed templates for Alacritty, Hyprland, Waybar, and other apps.
- Introduce Makima key remapper module and configuration.
- Add Voxtype and Walker configurations.
- Implement systemd power management and timeout optimizations.
- Add Nautilus-python extensions for LocalSend.
- Update branding assets and ASCII art integration.

bin/system/nomarchy-sudo-keepalive

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+# Prompt for sudo once and keep the credential alive in the background.
+# Source this script so the trap applies to the calling shell:
+#   source nnomarchy-sudo-keepalive
+
+sudo -v
+while true; do sudo -n true; sleep 60; done 2>/dev/null &
+SUDO_KEEPALIVE_PID=$!
+trap "kill $SUDO_KEEPALIVE_PID 2>/dev/null" EXIT