Week 5 Day 4: provider evaluation cost report

[utkarshp845]

Summary

• add an opt-in provider evaluation report that joins rubric outcomes, bounded telemetry, and estimated costs
• calculate cost per successful evaluated analysis only with complete cost data
• document the Day 4 workflow while keeping CI offline and cost-free

Validation

• python -m pytest -q
• python -m ruff check app cli tests
• python -m evals.run_evals