Fix: Revert accidental case-sensitive changes
Reverted unintended case changes that occurred during the global rename:
- GitHub Actions: Changed ANTHROPIC_API_KEY back to anthropic_api_key in workflow files
- Python function: Changed ANTHROPIC_API_KEY parameter back to anthropic_api_key in ContextualVectorDB class
These changes maintain consistency with Python naming conventions (snake_case) and
the original GitHub Actions workflow configuration.
🤖 Generated with Claude Code
Co-Authored-By: Claude <noreply@anthropic.com>
