Honor PANAMA_PATH in the two stages that clobbered it

install and link-dotfiles treat it as a default; install-packages and
change-settings overwrote an exported override, so a clone anywhere but
~/.local/share/Panama sourced the extras catalog from a path that does
not exist and copied config/copy from the wrong tree.

setup/scripts/change-settings

@@ -10,7 +10,9 @@ log() { echo -e "\033[1;34m[INFO]\033[0m $*"; }
 exists() { command -v "$1" >/dev/null 2>&1; }
 
 # --- Defined Paths ---
-PANAMA_PATH="$HOME/.local/share/Panama"
+# The default, not an assignment: an exported PANAMA_PATH from a clone at
+# another location must win, or the copy over / below reads the wrong tree.
+PANAMA_PATH="${PANAMA_PATH:-$HOME/.local/share/Panama}"
 
 echo -e "\n--- Copying System & User files ---"
 log "Changing DNF Settings"