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/appearance/nomarchy-theme-bg-set

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+# Sets the specified image as the current background
+
+if [[ -z $1 ]]; then
+  echo "Usage: nnomarchy-theme-bg-set <path-to-image>" >&2
+  exit 1
+fi
+
+BACKGROUND="$1"
+CURRENT_BACKGROUND_LINK="$HOME/.config/nnomarchy/current/background"
+
+# Create symlink to the new background
+ln -nsf "$BACKGROUND" "$CURRENT_BACKGROUND_LINK"
+
+# Kill existing swaybg and start new one
+pkill -x swaybg
+setsid uwsm-app -- swaybg -i "$CURRENT_BACKGROUND_LINK" -m fill >/dev/null 2>&1 &