`RecursiveIterator.stream()` emits `StreamException` for notes in inner streams

[jacobtylerwalls]

const n = new music21.note.Note("C#");
const m = new music21.stream.Measure();
m.append(n)
const p = new music21.stream.Part();
p.append(m);
const s = p.recurse().stream();

StreamException: An entry for this object is not stored in this Stream.

[mscuthbert]

I've totally forgotten how this works on m21p let alone here. Does it use .template?

[jacobtylerwalls]

No, it just does getOffsetInHierarchy and then a bunch of coreAppend.

I think this is the missing piece: https://github.com/cuthbertLab/music21j/blob/0d7aa31c48f7f697c18e6c3ee7d169d56150ff9b/src/music21/stream/iterator.ts#L167-L170