- Test 17: adds user to SelectedUsers
- Test 18: skips duplicates
- Test 19: null does nothing
- Test 20: user is auditable after selection
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Inject IGraphUserDirectoryService into UserAccessAuditViewModel (both constructors)
- Add IsBrowseMode toggle, DirectoryUsers collection, DirectoryUsersView with sort/filter
- Add LoadDirectoryCommand with progress reporting, cancellation, and error handling
- Add IncludeGuests toggle for in-memory member/guest filtering (no new Graph request)
- Add DirectoryFilterText for DisplayName/UPN/Department/JobTitle text search
- Add DirectoryUserCount computed property reflecting filtered view count
- Update OnTenantSwitched to clear all directory state
- Add 16 comprehensive unit tests covering all directory browse behaviors
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
