scripts: add cleanup-i3 and cleanup-sway uninstallers

Two POSIX sh scripts to undo a session install on a Void host: remove
session-exclusive packages (filtered to those actually installed),
exclusive dotfiles and runtime state, plus the emptty session entry.
Shared resources (dunst, rofi, alacritty, xfce4-screenshooter) are left
in place so the other session keeps working. Confirmation prompt before
any destructive action.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

scripts/cleanup-sway.sh

@@ -0,0 +1,93 @@
+#!/usr/bin/env sh
+# Remove sway session artifacts: exclusive packages, dotfiles, runtime state
+# and the emptty wayland-sessions entry. Shared resources with i3 (dunst,
+# rofi, alacritty, xfce4-screenshooter) are left untouched.
+
+set -eu
+
+SWAY_PACKAGES="
+cliphist
+kanshi
+swayfx
+swaybg
+swayidle
+swaylock
+SwayOSD
+Waybar
+wl-clipboard
+xdg-desktop-portal-wlr
+xorg-server-xwayland
+"
+
+SWAY_DOTFILES="
+$HOME/.config/sway
+$HOME/.config/waybar
+$HOME/.local/bin/start-sway
+$HOME/.cache/cliphist
+"
+
+EMPTTY_SESSION=/etc/emptty/wayland-sessions/sway.desktop
+
+confirm() {
+  printf '%s [y/N] ' "$1"
+  read -r answer
+  case "$answer" in
+    y|Y|yes|YES) return 0 ;;
+    *) return 1 ;;
+  esac
+}
+
+filter_installed() {
+  for p in $1; do
+    if xbps-query -p pkgver "$p" >/dev/null 2>&1; then
+      printf '%s\n' "$p"
+    fi
+  done
+}
+
+if ! command -v xbps-remove >/dev/null 2>&1; then
+  printf 'Error: xbps-remove not found (not a Void host?)\n' >&2
+  exit 1
+fi
+
+installed=$(filter_installed "$SWAY_PACKAGES" | tr '\n' ' ' | sed 's/ *$//')
+
+printf '== sway cleanup ==\n\n'
+printf 'Packages to remove (installed only):\n'
+if [ -n "$installed" ]; then
+  printf '  %s\n' $installed
+else
+  printf '  (none)\n'
+fi
+printf '\nDotfiles / state to remove:\n'
+for d in $SWAY_DOTFILES; do
+  if [ -e "$d" ] || [ -L "$d" ]; then
+    printf '  %s\n' "$d"
+  fi
+done
+printf '\nEmptty session entry:\n'
+if [ -e "$EMPTTY_SESSION" ]; then
+  printf '  %s\n' "$EMPTTY_SESSION"
+else
+  printf '  (absent)\n'
+fi
+printf '\nShared (NOT removed): dunst, rofi, alacritty, xfce4-screenshooter and their configs.\n\n'
+
+confirm 'Proceed?' || { printf 'Aborted.\n'; exit 0; }
+
+if [ -n "$installed" ]; then
+  # shellcheck disable=SC2086
+  sudo xbps-remove -Ry $installed
+fi
+
+for d in $SWAY_DOTFILES; do
+  if [ -e "$d" ] || [ -L "$d" ]; then
+    rm -rf -- "$d"
+  fi
+done
+
+if [ -e "$EMPTTY_SESSION" ]; then
+  sudo rm -f -- "$EMPTTY_SESSION"
+fi
+
+printf '\nDone.\n'