Integrate Black formatter with Bazel for local development

[mrkushalsm]

Hey! 👋

This PR adds Bazel integration for the Black Python formatter, addressing #226.

What's added

Two new bazel run targets:

# Fix formatting in-place
bazel run //:black_fix -- .

# Check formatting (shows diff, exits non-zero if changes needed)  
bazel run //:black_check

Changes

File	Description
MODULE.bazel	Added rules_shell and pip.parse extension for managing Black
BUILD	Added black_runner, black_fix, and black_check targets
requirements.txt	New file pinning black==24.8.0 (matching CI)
black_runner.py	Python entry point for Black
black_fix.sh	Shell wrapper for fixing formatting
black_check.sh	Shell wrapper for checking formatting

Note on implementation

The original issue suggested using sh_test for black_check, but I went with sh_binary instead. This is because bazel test runs in a sandbox that doesn't have access to the full source tree. Using bazel run for both commands gives consistent behavior and access to all project files.

Happy to discuss if you'd prefer a different approach!

Testing

Verified locally:

• ✅ bazel run //:black_check reports all 85 files as correctly formatted
• ✅ bazel run //:black_fix successfully reformats files
• ✅ Both commands respect the pyproject.toml exclusion for cached_parser.py

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[EricRahm]

Overall looks good, a few minor requests. Thanks for the contribution!

[mrkushalsm]

Hey @EricRahm!

Made the few minor changes you asked for, it was an oversight on my side for making those date mistakes and not keeping the shell and python files under scripts folder, have fixed it now.

Do review and let me know if anymore changes are needed!!

[mrkushalsm]

Sorry, forgot to change the BUILD file, do run the tests and check now!

[EricRahm]

Looks good, thanks for the contribution!

[mrkushalsm]

Thanks for providing this opportunity to me Eric, glad to have contributed!!