refactor: migrate from shell-based sync to mise dotfiles management

- Replace sync-config/sync-script with mise.toml [dotfiles] directives
- Convert installer scripts to mise tasks (shells, desktop, theme, webapps)
- Remove config/nvim-old (deprecated neovim config)
- Add omarchy theme system with multi-app configs (btop, hyprland, kitty, foot, tmux, etc.)
- Move SSH hosts to config.d/* include pattern
- Add Tera templates for dynamic config generation (git-local, dofiles.conf)
- Update pi agent settings (0.80.10, packages list)
- Add mise tasks for pi plugin setup and nvim tooling

packages/sjb-desktop.packages

@@ -98,6 +98,7 @@ xdg-desktop-portal-hyprland
 xdg-user-dirs
 xorg-xwayland
 xournalpp
+yaru-icon-theme
 zathura
 zathura-pdf-poppler
 zed