Switch to emacs-wayland on Arch, use package-provided emacs.service

- emacs → emacs-wayland in arch_profile_packages
- Remove custom emacs.service deployment: replace full .config/systemd/user/
  directory copy with individual service files (rclone-pcloud, syncthing)
- Remove emacs.service from desktop_systemd_user_services
- Enable package-provided /usr/lib/systemd/user/emacs.service via symlink
  in profile_desktop_gnome

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

ansible/inventory/group_vars/arch.yml

@@ -85,7 +85,7 @@ arch_profile_packages:
   - deluge
   - dnsmasq
   - edk2-ovmf
-  - emacs
+  - emacs-wayland
   - ffmpegthumbnailer
   - firefox
   - fontconfig
@@ -134,6 +134,5 @@ enabled_services:
   - ufw
 
 desktop_systemd_user_services:
-  - emacs.service
   - syncthing.service
   - rclone-pcloud.service