Add post-processing for bhkListShape subshapes

bhkListShape contains a list of subshape references that need to be
resolved after initial parsing. Without calling postRecordList(), the
mSubshapes list would contain unresolved RecordPtrs.

This adds the missing post() override to properly load subshape data,
consistent with other NIF record types that contain RecordPtr lists.

components/nif/physics.cpp

@@ -770,6 +770,11 @@ namespace Nif
             filter.read(nif);
     }
 
+    void bhkListShape::post(Reader& nif)
+    {
+        postRecordList(nif, mSubshapes);
+    }
+
     void bhkCompressedMeshShape::read(NIFStream* nif)
     {
         mTarget.read(nif);

components/nif/physics.hpp

@@ -730,6 +730,7 @@ namespace Nif
         std::vector<HavokFilter> mHavokFilters;
 
         void read(NIFStream* nif) override;
+        void post(Reader& nif) override;
     };
 
     struct bhkCompressedMeshShape : public bhkShape