PF_SAN=address builds the punktfunk-core staticlib on nightly with
-Zsanitizer/-Zbuild-std and the C harness with clang -fsanitize, so ASAN
instruments both sides of the boundary at once and LSAN (detect_leaks=1)
becomes the first automated check on abi.rs's Box::into_raw/from_raw leak
contract. Verified on the .25 box: green run passes byte-exact; deleting
one punktfunk_session_free() in the harness makes LSAN report the 308
Rust-side allocations behind the handle and the script exit 1.
The harness binary moves from mktemp to target/ — a debug+ASAN static
binary can exceed a tmpfs /tmp (it did, on .25's 3.6G tmpfs).
enricobuehler
e20b614059