Build Admin Dashboard Screen with KPI Grid

Implement AdminDashboardScreen as a StatelessWidget consuming AdminPortalBloc via BlocSelector for efficient rebuilds. Map DashboardStats fields to a List in a pure helper function (mapStatsToKpiTiles) outside the build method to keep build() clean. Use LayoutBuilder at the grid level only — not the full screen — to determine column count. For drill-down navigation, define typed route parameters that carry the current org scope ID so the destination screen can restore scope context.

The OrgHierarchyNavigator should be placed in a collapsible top panel (e.g., ExpansionTile or AnimatedContainer) on mobile to avoid consuming too much vertical space. The page header 'All Organisations' / '{Org Name}' text should be a dedicated ScopeBadge widget that reads scope from BLoC state — keep it decoupled from the grid. For the NHF use case, the dashboard is the first screen admins see after login — ensure time-to-first-meaningful-paint is fast by showing skeleton tiles immediately while data loads asynchronously. Avoid placing BLoC event dispatch calls inside build() — use initState (in StatefulWidget) or a post-frame callback for initial data load.

Widget tests using flutter_test with ProviderScope and BlocProvider overrides. Cover: (1) initial render shows shimmer tiles in loading state, (2) loaded state renders correct number of KPI tiles with correct values, (3) error state shows retry button, (4) tapping retry dispatches LoadDashboardStats event, (5) scope selection updates page header text, (6) tapping a KPI tile triggers correct navigation route, (7) grid shows 2 columns at 375px width, (8) grid shows 4 columns at 1440px width, (9) WCAG semantics check (all tiles have readable semantic labels). Integration test: mount full screen, simulate scope change, assert all tiles update with new values. Golden tests for: loaded state (desktop), loaded state (mobile), error state.