Follow-up to #66, found in the unchanged pinned Bun transpiler corpus at source pin 4982b91e3702094330f3be3883354c52b8c01323.
Async Bun.Transpiler.transform() must retain an owned copy of Uint8Array input before dispatching work. Detaching and reusing the caller buffer while the task is in flight currently lets worker parsing observe replacement bytes.
The logical upstream behavior is represented by Bun commit cd1ad59994: copy buffer input before the worker hop, account the owned memory, release the protected caller buffer, and let the async task own the encoded slice.
Acceptance: the unchanged test transform() result is unaffected by detaching the input ArrayBuffer while the task is in flight passes, repeated detached-input stress stays deterministic, synchronous transform remains unchanged, and the full transpiler corpus gains one pass without filtering or test edits.