eliminate path-tree-based keying of debug info on frontend; use dbgi-layer-defined debug info keys, which can be more robust to changes to the same debug info path across time (e.g. during hot reloads

src/mule/mule_peb_trample_reload.c

@@ -1,10 +1,13 @@
 __declspec(dllexport) int
 loop_iteration(int it)
 {
+  return 111;
+#if 0
   int sum = 0;
   for(int i = 0; i < 1000; i += 1)
   {
     sum += it*i;
   }
   return sum;
+#endif
 }