Remove Sway from the playbook, keep Noctalia configs

Drop the profile_desktop_sway role (tasks, templates), all Sway
dotfiles, desktop_sway_* vars, and wayland-sessions emptty path.
Noctalia dotfiles are preserved and deployed via desktop_void_dotfiles
on Void hosts; noctalia_bar_monitors/noctalia_screen_overrides kept
as config vars. Only i3 remains as the Void desktop session.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

dotfiles/desktop/.local/bin/start-sway-session

@@ -1,28 +0,0 @@
-#!/bin/sh
-
-[ -r /etc/profile ] && . /etc/profile
-[ -r "$HOME/.profile" ] && . "$HOME/.profile"
-[ -r "$HOME/.config/sway/session-env" ] && . "$HOME/.config/sway/session-env"
-
-set -eu
-
-session_name=sway
-
-export XDG_CURRENT_DESKTOP="$session_name"
-export XDG_SESSION_DESKTOP="$session_name"
-export XDG_SESSION_TYPE=wayland
-export SSH_AUTH_SOCK="$HOME/.local/state/ssh-agent/socket"
-
-if [ "${SWAY_UNSUPPORTED_GPU:-0}" = "1" ]; then
-  set -- sway --unsupported-gpu
-else
-  set -- sway
-fi
-
-exec dbus-run-session sh -eu -c '
-  umask 077
-  printf "%s\n" "$DBUS_SESSION_BUS_ADDRESS" > "$HOME/.dbus-session-bus-address"
-  gpgconf --launch gpg-agent
-  "$HOME/.local/bin/update-turnstile-env"
-  exec "$@"
-' sh "$@"