chore: ignore Python bytecode

[Vilin97]

Running scripts/check_golf.py locally leaves __pycache__/ behind, and one .pyc already slipped into a commit once (via #1400, since removed on master). Add __pycache__/ and *.pyc to .gitignore so it cannot happen again.

🤖 Generated with Claude Code

[github-actions]

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[jstoobysmith]

Approved