[teamchong]

Avoid unnecessary ArrayBuffer copies across jsonCompatibleWithBytes and MessagePort (structuredClonable) transports:

1. Zero-copy jsonCompatibleWithBytes serialization (Devaluator.devaluateImpl):

   • In fix: send only a byte view's own bytes over structured-clone transports #287, partial Uint8Array views (bytes.byteOffset !== 0 || bytes.byteLength !== bytes.buffer.byteLength) were copied with new Uint8Array(bytes) at both structuredClonable and jsonCompatibleWithBytes levels so MessagePort.postMessage wouldn't clone an entire shared backing buffer (such as Node's Buffer pool or WebAssembly.Memory).
   • Custom jsonCompatibleWithBytes transports inspect [bytes.buffer, bytes.byteOffset, bytes.byteLength] directly rather than structured-cloning bytes.buffer, so Devaluator now keeps the exact view at jsonCompatibleWithBytes level and only copies un-transferred partial views at structuredClonable level.

2. Zero-copy ArrayBufferView deserialization (Evaluator.evaluateImpl):

   • Previously, Evaluator always called bytes.buffer.slice(bytes.byteOffset, bytes.byteOffset + bytes.byteLength) before constructing typed arrays or DataView, even when bytes was already a raw Uint8Array at jsonCompatibleWithBytes or structuredClonable level.
   • Now, when the incoming payload is a raw Uint8Array (not base64-decoded into Node's shared Buffer pool), native endianness is little-endian (or elementSize === undefined), and bytes.byteOffset is aligned to elementSize, typed array and DataView views are constructed directly on (bytes.buffer, bytes.byteOffset, ...) without slicing.
   • ArrayBuffer payloads continue to slice subviews so byteLength and indexable bounds match the serialized view.

3. Opt-in transferable ArrayBuffers over MessagePort (transferArrayBuffer):

   • Added transferArrayBuffer(viewOrBuffer) to mark an ArrayBuffer (or the backing ArrayBuffer of an ArrayBufferView) for zero-copy transfer over MessagePort transports.
   • Devaluator preserves partial views on marked buffers without copying, and MessagePortTransport.send() collects and consumes marked ArrayBuffers into the postMessage(message, transfer) transfer list (with a zero-cost boolean fast-path when transferArrayBuffer() has not been called).

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