stream: error callbacks after destroy during write/final

[cjc0013]

Writable streams can be destroyed inside user-provided _write() or _final() implementations before their callback runs. In that gap, the callback could previously continue the write/final completion path as a success even though the stream had already been destroyed.

This change checks for destruction when those callbacks return. If the stream was destroyed without an explicit error, the write or end callback receives ERR_STREAM_DESTROYED, which follows the issue guidance to cancel the remaining completion work and turn a silent destroy into an error.

Validation: node --check lib/internal/streams/writable.js, node --check test/parallel/test-stream-writable-destroy.js, node --check test/parallel/test-stream-writable-final-destroy.js, and git diff --check.

Refs: #39030

[nodejs-github-bot]

Review requested:

• @nodejs/streams