Session validation now also checks created_at so the 12-hour cap holds
while expires_at is still in the future. Genre seed avoids ON CONFLICT,
which burns SMALLSERIAL values on every startup.
Spec covers data model, API, auth, frontend, error handling, and testing.
ADR-0001 records PBKDF2 + pepper (FIPS) over argon2; ADR-0002 records
revocable server-side sessions over Flask's signed cookie.
mroberts