Fix flask initdb error: migrate to Authlib 1.x

[wadelhw]

Summary

Fixes #19 — flask initdb fails with ImportError: cannot import name '_app_ctx_stack' from 'flask' when using modern Flask (3.x) with Authlib 0.13.

Root Cause

Authlib 0.13 imports flask._app_ctx_stack, which was removed in Flask 2.3+. The unpinned Flask and Flask-SQLAlchemy dependencies resolve to Flask 3.1.x and Flask-SQLAlchemy 3.1.x, causing the import failure at app startup.

Changes

requirements.txt

• Updated Authlib==0.13 → Authlib>=1.0

website/oauth2.py — Migrated to Authlib 1.x API:

• create_authorization_code → save_authorization_code (new signature: code + request instead of client + grant_user + request)
• parse_authorization_code → query_authorization_code
• exists_nonce now uses request.payload.client_id (Authlib 1.x request structure)
• get_jwt_config now receives client parameter for OpenIDCode, ImplicitGrant, HybridGrant
• Authorization code helper updated for new request object attributes (request.client, request.payload, request.user)

website/routes.py

• Fixed Blueprint(__name__, 'home') → Blueprint('home', __name__) (Flask 3.x rejects dots in Blueprint names)
• validate_consent_request → get_consent_grant (Authlib 1.x rename)

Testing

• pip install -r requirements.txt installs successfully (Authlib 1.6.9, Flask 3.1.3, Flask-SQLAlchemy 3.1.1)
• flask initdb runs without errors and creates the SQLite database
• App imports and all OAuth2 routes register correctly