refactor(pypi): implement PEP508 compliant marker evaluation

[aignas]

This implements the PEP508 compliant marker evaluation in starlark and
removes the need for the Python interpreter when evaluating requirements
files passed to pip.parse. This makes the evaluation faster and allows
us to fix a few known issues (#2690).

In the future the intent is to move the METADATA parsing to pure
starlark so that the RequiresDist could be parsed in starlark at the
macro evaluation or analysis phases. This should make it possible to
more easily solve the design problem that more and more things need to
be passed to whl_library as args to have a robust dependency parsing:

• [pypi] Support python micro version in env marker based dependency evaluation #2319 needs the full Python version to have correct cross-platform
  compatible METADATA parsing and passing it to Python and back makes
  it difficult/annoying to implement.
• Parsing the METADATA file requires the precise list of target
  platform or the list of available packages in the requirements.txt.
  This means that without it we cannot trim the dependency tree in the
  whl_library. Doing this at macro loading phase allows us to depend
  on .bzl files in the hub_repository and more effectively pass
  information.

I can remotely see that this could become useful in py_wheel or an building
wheels from sdists as the environment markers may be present in various source
metadata as well. What is more uv.lock file has the env markers as part of
the lock file information, so this might be useful there.

Work towards #2423
Work towards #260
Split from #2629

[aignas]

Refreshed the lockfile before and after the change:

bazel mod deps --lockfile_mode=refresh

And saw no difference in entries except for the expected:

$ diff MODULE.bazel.lock{before,after}
161c161
<         "bzlTransitiveDigest": "HtK14jTL6GRmVkjtcDvWJ+J5LmpFcDz5iGWjGt4RORc=",
---
>         "bzlTransitiveDigest": "1YngqOV37S3bLvhBu3wQ+h/bYrkyRpmh11ur6JIqqu0=",
164d163
<           "@@+internal_deps+pypi__packaging//packaging-24.0.dist-info/RECORD": "be1aea790359b4c2c9ea83d153c1a57c407742a35b95ee36d00723509f5ed5dd",
167,168d165
<           "@@//python/private/pypi/requirements_parser/resolve_target_platforms.py": "42bf51980528302373529bcdfddb8014e485182d6bc9d2f7d3bbe1f11d8d923d",
<           "@@//python/private/pypi/whl_installer/platform.py": "763d705ceaa41c87d8a6cfe8c6bc261a20881628b96f2fb4c4fef4b9befa53fe",

[aignas]

OK, I think this is ready to be merged. This is probably already higher fidelity/more robust than the Python impl of platform.py in our repo.