feat(uv): multiversion packages and extras support

[arrdem]

The original uv extension prototype treated the uv.lock file as "requirements.txt++" which enormously undersells what uv can and will put into the lockfile.

One example of which is that in cases where the user provided marker dependent version constraints, uv will happily solve the constraints for all cases of the markers and generate a lockfile which captures the version disambiguated requirement graph for all configurations, and propagates marker expressions as needed.

A related example is that uv retains extras and their activations explicitly as part of the graph rather than simply listing the reach set of requirements after extras have all been activated, which would discard that information.

Fixes #798, #797, #794, #792, #791, #773

Changes are visible to end-users: yes

• Searched for relevant documentation and updated as needed: yes
• Breaking change (forces users to change their own code or config): no
• Suggested release notes appear below: yes

The experimental uv extension has seen significant changes to address a number of outstanding bugs.

• Multiple versions of a single package are now supported
• [dependency-groups] are now interpreted as defining build/venv configurations
• Extra activations are propagated correctly

Test plan

• New test cases added

Remaining work

• Need to re-validate the Gazelle manifest generation
• Need to add a test covering [Bug]: uv extension crashes on wheels without hash digests from private registries #790
• Need to add a test covering [Bug]: uv extension does not filter editable packages, causing dangling dependency references #791
• Need to add a test covering [Bug]: When using uv hub, internal dependencies between pyproject workspaces throw an analysis error #789
• Need to add a test covering fix: filter editable packages and prune dangling dependency references #794

[aspect-workflows]

Bazel 8 (Test)

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Bazel 9 (Test)

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Bazel 8 (Test)

e2e

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Bazel 9 (Test)

e2e

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Bazel 8 (Test)

examples/uv_pip_compile

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[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ arrdem
❌ aspect-marvin
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[arrdem]

There's more work to be done here, but as-is this is a substantial step in the right direction. Declaring victory and will fast-follow other work.