- ps5::heap: global allocator over the SDK's libc malloc/posix_memalign
- ps5:🧵 spawn/join over pthreads, plus a pthread Mutex
- build-std now includes alloc; payloads without the feature are unchanged
- examples/threads: 4 threads sum heap Vecs into an Arc<Mutex<u64>>
(tested on CFI-1215A, fw 13.60: "threads OK")
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>