Fix AI questionnaire generation and add progress bars

[codoom1]

What changed

• Replaces dozens of sequential questionnaire AI calls with one bounded Structured Outputs request.
• Generates 1–5 validated, focused AI questions and merges them into the complete rules-based questionnaire.
• Uses one quota unit per questionnaire request and sends a privacy-preserving safety identifier.
• Falls back visibly to a complete rules-based questionnaire if AI is unavailable.
• Adds staged progress overlays to statistical model selection and questionnaire generation.
• Adds responsive, accessible progress styling and regression coverage.

Root cause

Production logs showed questionnaire generation repeatedly enhancing individual questions and generating each question type in separate OpenAI calls. Several calls exceeded the 400-token output ceiling, and Vercel ultimately terminated the request at its 60-second runtime limit.

Validation

• pytest -q tests: 135 passed
• Focused integration and route tests: 50 passed
• Blocking flake8 checks: 0 errors
• JavaScript syntax check: passed
• git diff --check: passed

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
statistical-model-suggester	Ready	Preview, Comment	Jul 25, 2026 1:04am

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.