feat: add omarchy theme template system with management scripts

- New default/themed/ templates (alacritty, btop, foot, ghostty, helix,
  hyprland, hyprlock, kitty, mako, obsidian, rofi, swayosd, tmux,
  walker, waybar, keyboard.rgb, gum.env, etc.)
- Add omarchy-* theme management scripts (install, refresh, set, remove,
  update, bg-set, colors-from-alacritty, current, etc.)
- Add omarchy restart/hook scripts (btop, hyprctl, hypridle, mako, tmux)
- Add installer/environment.sh for shared env vars
- Add 19 theme directories with colors.toml, vscode.json, backgrounds,
  and app-specific configs (catppuccin, everforest, gruvbox, nord,
  tokyo-night, rose-pine, etc.)
- Update bing-wallpaper script to use new .config/omarchy path

script/bing-wallpaper

@@ -9,7 +9,7 @@ offset=0
 [[ "$1" =~ [1-9][0-9]*$ ]] && offset=$1
 
 BACKGROUNDS_DIR="$HOME/Sync/Shared/wallpapers"
-CURRENT_BACKGROUND_LINK="$HOME/.local/share/themes/current/background"
+CURRENT_BACKGROUND_LINK="$HOME/.config/omarchy/current/background"
 
 url_preffix="http://www.bing.com"
 xml_url="https://cn.bing.com/HPImageArchive.aspx?format=xml&idx=$offset&n=10&nc=1612409408851&pid=hp&FORM=BEHPTB&uhd=1&uhdwidth=3840&uhdheight=2160"