stream: async iterator improvements

Includes a few different fixes separated into commits:

• Adds support to create async iterators from v1 streams.
• Normalize destroying non conforming streams.
• Implement throw on the iterator.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines