Replace server-side session backends (redis, file, database, memcached)
with client-side signed cookie sessions. Users will need to
re-authenticate after deploy.
- Rewrite rc_beaker.py to use pyramid.session.SignedCookieSessionFactory
- Gut user_sessions.py to cookie-only stub
- Drop beaker.container from memory_lru_dict.py (pure repoze.lru)
- Migrate ini configs from beaker.session.* to session.* namespace
- Remove beaker==1.13.0 from requirements.txt
- Remove beaker.backends entry points from pyproject.toml
- Preserve backward-compat fallbacks for encryption key resolution
russell@unturf.com
4f73837822