- IamServiceContext: add EF column mappings for ApplicationRole private
fields (description, is_system_role, created_at) matching new DB columns
- GetRolesQueryHandler: JOIN with UserRoles to compute real user count
per role instead of returning 0
- RoleDto/RoleResponse: add UserCount field
- DB: added columns description, is_system_role, created_at to roles table
with correct data for all 8 roles
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>