refactor(dotfiles): rename system/ to common/ and remove unused configs

Rename dotfiles/system to dotfiles/common for clarity - indicates
shared dotfiles used across all desktop environments (DWM, Hyprland).

Removed config directories for uninstalled applications:
- ghostty (using different terminal)
- lf (using ranger instead)
- mopidy (using mpd instead)
- nitrogen (X11-only, obsolete for Wayland)
- pychess (not installed)
- JetBrains (not installed via archsetup)
- youtube-dl (using yt-dlp with different config location)

Kept audacious config for potential future use.

Updated all references in archsetup, CLAUDE.md, todo.org, and
validation.sh.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

1 files changed, 0 insertions, 20 deletions

diff --git a/dotfiles/system/.local/share/applications/emacsclient-mail.desktop b/dotfiles/system/.local/share/applications/emacsclient-mail.desktop
deleted file mode 100644
index 6efcf61..0000000
--- a/dotfiles/system/.local/share/applications/emacsclient-mail.desktop
+++ /dev/null
@@ -1,20 +0,0 @@
-[Desktop Entry]
-Categories=Network;Email;
-Comment=Emacs is my mail client
-Exec=sh -c "exec emacsclient --alternate-editor= --display=\\"\\$DISPLAY\\" --eval \\\\(message-mailto\\\\ \\\\\\"%u\\\\\\"\\\\)"
-Icon=emacs
-Name=Emacs (Mail, Client)
-MimeType=x-scheme-handler/mailto;
-NoDisplay=true
-Terminal=false
-Type=Application
-Keywords=emacsclient;
-Actions=new-window;new-instance;
-
-[Desktop Action new-window]
-Name=New Window
-Exec=/usr/bin/emacsclient --alternate-editor= --create-frame --eval "(message-mailto \\"%u\\")"
-
-[Desktop Action new-instance]
-Name=New Instance
-Exec=emacs -f message-mailto %u