Schema v3: add is_public column to table_registry (default true).
src/rbac.py: can_access_table() checks admin bypass, public flag,
explicit permissions, wildcard bucket permissions.
API enforcement:
- manifest: filters tables by user access
- download: 403 if no access
- catalog: filters table list
- query: validates referenced tables against allowed list
New admin permissions API (/api/admin/permissions) for grant/revoke.
28 access control tests + 733 total tests passing.
New src/rbac.py: Role enum, hierarchy, get_user_role(), has_role(),
is_admin(), is_km_admin(), has_dataset_access(), set_user_role().
webapp/auth.py: admin_required + km_admin_required now use DuckDB
roles instead of Linux groups (pwd.getpwnam + sudo/data-ops check).
app/auth/dependencies.py: imports Role from src/rbac.py (single source).
11 RBAC tests passing.