All 12 E2E workflows used `paths: ['**']` which triggered on every file
change — docs, configs, experiments, etc. This caused ~140-200 min of
compute per push event (18+ parallel workflows).
Now E2E tests only trigger when relevant source code changes:
- Python E2E: codeflash/**, tests/**, pyproject.toml, uv.lock, workflow files
- JS E2E: same + packages/**
- Java E2E: already had proper path filters (no change needed)
Estimated savings: ~$150-200/mo in CI compute.
