4e9ed97b05
- New backend: Group + GroupMembership models, schemas, CRUD router at /api/admin/groups (list, create, get detail, update, delete, add/remove members) - New Alembic migration: groups and group_memberships tables - Frontend: Admin sidebar item is now an expandable accordion with Users and Groups sub-items; AdminPage redirects to /admin/users; new AdminUsersPage and AdminGroupsPage with inline member management panel - API client: 7 new group functions + TypeScript types Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>