perf(uv): deduplicate wheel installs

[zbarsky-openai]

Depends on #1348.

Summary

• Share concrete wheel-variant install repositories across lock universes when metadata, ordered wheel candidates, and exclusions match.
• Keep patched variants project-local and preserve order-sensitive wheel selection.
• Add focused coverage for ordering, exclusions, and patched variants.

Validation

• bazel run //:buildifier -- /tmp/rules-py-dedup/uv/private/extension/defs.bzl /tmp/rules-py-dedup/uv/private/extension/test_defs.bzl /tmp/rules-py-dedup/uv/private/whl_install/repository.bzl
• bazel test //uv/private/extension:shared_whl_variant_key_tests

[CLAassistant]

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[tamird]

This contains the full lazy-metadata change and currently repeats its causal CI failures. There is also an integration hole with the approved exclude_glob API: wheel variants receive the filter, but an sdist fallback selected through the public repository does not. Please extract/rebase after #1348, preserve the filter for both install paths, and add a real two-lock dedupe plus sdist-filter regression.

[tamird]

exclude_glob is forwarded to each concrete wheel variant above, but it is absent from this public-selector install_kwargs. If resolution falls back to an sdist, the selected install silently keeps files the caller explicitly excluded. Please forward the filter here too and exercise an actual sdist fallback; the current key tests fabricate exclude_glob and do not prove the selected install is filtered.