- Guard all session.save() calls with hasattr checks for CookieSession
compatibility (CookieSession auto-saves via response callbacks)
- Guard beaker-specific _set_cookie_expires and _update_cookie_out in
login views
- Defer ldap scope_labels to property to avoid class-level AttributeError
when python-ldap is not installed
- Add vcsserver stub package to allow imports without full vcsserver
- Add rc_license stub for CE edition (no license management)