feat(npc, nav): 17.5 - a person walks by the world's way where it has one (NpcWorld.way: the next corner toward the target, asked every half second, on reaching it or for a new target; the errand begins only at the target itself; the step round and the give-up stay the fallback), way_test round a wall; and ludic.nav reads a mesh file into the shim's own memory and frees it once parsed, so loading a map leaves nothing in Ludic's never-freed heap

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.nav/native/shim/nav_shim.cpp

@@ -7,6 +7,7 @@
 #include <DetourNavMeshQuery.h>
 #include <DetourCommon.h>
 #include <cstring>
+#include <cstdlib>
 #include <cmath>
 #include <vector>
 

packages/ludic.nav/native/shim/nav_tiles.inl

@@ -100,3 +100,12 @@ NAV_SHIM void *nav_load(const unsigned char *buf, int size) {
   }
   return nav_open(mesh);
 }
+
+// a file read straight into the shim's own memory rather than a Ludic slice (which is never given
+// back): nav_stage hands out the room, nav_load_staged parses it and frees it, whatever the outcome
+NAV_SHIM unsigned char *nav_stage(int size) { return size > 0 ? static_cast<unsigned char *>(malloc(size)) : nullptr; }
+NAV_SHIM void *nav_load_staged(unsigned char *buf, int size) {
+  void *h = buf ? nav_load(buf, size) : nullptr;
+  free(buf);
+  return h;
+}