Foundation & Identity backend for ThoughtSync:
- Quart app factory (create_app) with /api/health + SPA history-fallback
- async SQLAlchemy 2.0 + asyncpg engine/session (lazy; boots without a DB)
- native email+password auth via signed-cookie session (register/login/logout/me
+ login_required guard); bcrypt password hashing (72-byte safe)
- multi-user sharing-ACL spine (rule 47): users, groups, group_members, and a
polymorphic shares table + visible_to_user() SQL predicate (owner OR direct
share OR group share) that M1's notes will scope through
- Alembic async env (adapted from family pattern) + 0001 foundation migration
- DB-free unit tests (app/health/auth-guard, password roundtrip, ACL compile)
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FRgehjoz7Yv8LkUfADxACm
