This PR adds support for `obj2yaml` and `yaml2obj` to generate minidumps
that have a Memory64List stream. This is a prerequisite to #101086.
Worth noting
- ~~const dropped on minidumps so we could cache a MemoryDescriptor_64
to it's actual offset, preventing the need to loop multiple times~~
- doesn't reuse the existing `ListStream` code in some places, because
the Memory64List has a different width size field (unsigned 64), and a
larger header than all the other streams. I determined refactoring the
existing code to support Mem64 would be worse than supporting the
special case.