Support for Closing Statement Iterator

Currently, better-sqlite3 allows stopping an active iterator by calling return(). This ensures clean-up and halts further reads. Here's an example:

const stmt = db.prepare("SELECT * FROM organizations"); // This has 100k rows
const iter = stmt.iterate();
const row = iter.next();

if (cancelTriggered) {
  iter.return(); // Stop reading and perform clean-up
}

Since we don't yet support return(), an alternative is to manually exhaust the iterator:

if (cancelTriggered) {
  for (const _row of iter) {}
}

Would it be possible to add support for return() to simplify the process? Thanks!

Start by locating the implementation of stmt.iterate() and the iterator methods used by iter.next() in the JavaScript API. Trace how iteration cleanup currently works, then verify that iter.return() stops further reads and performs the same cleanup as manually exhausting the iterator.