Preserve Git repository URLs in direct URL metadata (#19590)
## Summary
We now preserve the supplied Git repository URL when serializing
`direct_url.json` metadata for both repository sources and archives
stored within a Git repository.
While adding Git archive dependencies in #10072, we split the Git URL
representation but serialized the canonical repository identity rather
than the original URL. As a result, URLs such as
`git+ssh://git@github.com/phytec/phytec-eeprom-flashtool.git` lost the
username and `.git` suffix in `uv pip freeze` output.
This restores original URL serialization for both Git variants and
restores or adds coverage for installs, Git reference updates, and Git
LFS transitions. The affected integration tests, `uv-pypi-types` tests,
workspace Clippy, and `prek` pass with the fix.
Closes https://github.com/astral-sh/uv/issues/19587.
