Stream zip archive when fetching non-range-request metadata (#1792)
## Summary
If a registry doesn't support range requests, then today, we download
the entire wheel to disk and then read the metadata from the downloaded
archive. This PR instead modifies the registry client to stream the
zipfile and stop as soon as it's seen the metadata, which should be more
efficient.
Closes https://github.com/astral-sh/uv/issues/1596.
## Test Plan
Made this the _only_ path for downloading metadata; verified that the
test suite passed.
