Update CLAUDE.md and README.md: fix monthly schedule description

Change monthly benchmark to run on 1st of each month

Add GitHub Actions monthly benchmark with email delivery

Update docs: parallel execution, resumable runs, rate limiting

Fix OpenAI retry to skip auth errors, show key length in diagnostics

Add thread-safe rate limiting and verbose error messages

Parallelize benchmark execution with ThreadPoolExecutor

Add resume and reset for interrupted benchmark runs

Update CLAUDE.md and README with deployment and auth details

Add password protection to all pages

Add detailed secrets diagnostics for Streamlit Cloud

Add API key diagnostics and graceful error handling

Fix all API clients to resolve keys lazily for Streamlit Cloud

Fix Streamlit Cloud secrets access

Add Streamlit Cloud support