Initial import: chezmoi source for CachyOS + Umbriel + Noctalia

Imported from prdlk/dotfiles master (efdd827). Drops the niri, Hyprland/Omarchy,
macOS, and Blume docs-site layers; docs/ is plain Markdown.

dot_config/bash/functions/ghn.bash

@@ -0,0 +1,6 @@
+# Create a repo (prad.codes/github.com) + cd; logic lives in ~/.local/bin/ghn.
+ghn() {
+    local dir
+    dir=$(command ghn "$@") || return
+    cd "$dir" || return
+}