installer: split runtime and installer paths in finalizer

install/helpers/logging.sh

@@ -118,8 +118,9 @@ run_logged() {
 
   echo "[$(date '+%Y-%m-%d %H:%M:%S')] Starting: $script" >>"$OMARCHY_INSTALL_LOG_FILE"
 
-  # Use bash -c to create a clean subshell
-  bash -c "source '$script'" </dev/null >>"$OMARCHY_INSTALL_LOG_FILE" 2>&1
+  # Use a clean subshell, but keep errexit so failures inside sourced scripts
+  # cannot be hidden by a later successful command in the same script.
+  bash -eE -c 'source "$1"' bash "$script" </dev/null >>"$OMARCHY_INSTALL_LOG_FILE" 2>&1
 
   local exit_code=$?