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, 56 insertions, 0 deletions

diff --git a/dotfiles/common/.config/picom.conf b/dotfiles/common/.config/picom.conf
new file mode 100644
index 0000000..0b65df7
--- /dev/null
+++ b/dotfiles/common/.config/picom.conf
@@ -0,0 +1,56 @@
+# opacity-rule = [
+#     "85:class_g = 'XTerm'",
+#     "85:class_g = 'Alacritty'",
+#     "85:class_g = 'xterm-kitty'",
+#     "85:class_g = 'URxvt'",
+#     "85:class_g = 'tabbed'",
+# ];
+#    "85:class_g = 'st-256color'",
+#    "85:class_g = 'Emacs'",
+
+# Blur
+blur:
+{
+  method = "dual_kawase";
+  strength = 2;
+}
+
+wintypes:
+{
+  normal = { blur-background = true; };
+  splash = { blur-background = false; };
+};
+
+# Fading
+fading = false;
+fade-in-step = 0.07;
+fade-out-step = 0.07;
+fade-exclude = [ ];
+
+# Other
+corner-radius = 10.0;
+round-borders = 1;
+mark-wmwin-focused = true;
+mark-ovredir-focused = true;
+detect-rounded-corners = true;
+rounded-corners-exclude = [
+                        "class_g = 'dwm'",
+                        "class_g = 'dwmsystray'",
+                        "window_type = 'dock'"
+                        ];
+detect-client-opacity = true;
+
+vsync = true;
+dbe = false;
+unredir-if-possible = true;
+detect-transient = true;
+detect-client-leader = true;
+invert-color-include = [ ];
+
+# GLX backend
+backend = "glx";
+glx-no-stencil = true;
+glx-copy-from-front = false;
+use-damage = true
+glx-no-rebind-pixmap = true;
+