A chunk's trunks and boulders put in and taken out made a new shape each time and freed none. The
table is by the body's index, made once at the world's size. tests/reuse_test: 1000 owned bodies put
and removed hold no more shapes and 32 bytes of heap.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
