Workers

Fixed a parked move-later alarm desynchronizing the scheduled alarm, and hardened TypeScript streams to treat undefined IdentityTransformStream chunks as no-op writes, accept bare SharedArrayBuffer chunks in TextDecoderStream, and settle compression writes or closes cut short by a cancel. Also bumps V8 to 15.6 and returns IteratorResult<T, undefined> in SqlStorageCursor.next.

Fixed re-entrancy bugs in tee branch close handling, multiple algorithm clearance/re-entrancy issues, and a detached TransformStream native writable now closes and rejects its pending writes. Also introduced a V8 startup-snapshot pipeline and observer hooks for isolate cost attribution, plus TS readable stream queue clamping and precise UTF-8 length sizing.