Refresh Features

[slott56]

The fix for issue #141 in PR #170 also requires refresh of the Features.

Since The CEL Spec has also moved to v0.25.2, all the .textproto sources need to be updated.

[Quantum0uasar]

Happy to help with the .textproto refresh for CEL spec v0.25.2. I can:

1. Pull the updated conformance test .textproto files from the upstream google/cel-spec repo at tag v0.25.2
2. Run the existing test suite to identify any newly failing tests or spec changes that need corresponding fixes in the Python implementation
3. Open a PR with the updated files and any required implementation adjustments

Is PR #170 already merged? If so, I can base off main and proceed with the spec update.

[slott56]

Yes #170 is merged.