feat: Initial commit for DorkNet Admin Mobile app

- Implemented main application structure using .NET MAUI.
- Added App class to manage navigation between Login and Admin pages.
- Created AppDesign class for consistent UI styling.
- Developed pages: LoginPage, DashboardPage, PlayersPage, RoomsPage, SettingsPage, and AdminTabbedPage.
- Integrated AdminApiClient for API interactions and SecureAdminSettings for secure storage of sensitive data.
- Configured Android and iOS platform-specific files including manifest and app delegate.
- Added README with build instructions and authentication details.

DorkNet.AdminMobile/Pages/AdminTabbedPage.cs

@@ -0,0 +1,23 @@
+using Microsoft.Maui.Controls;
+using DorkNet.AdminMobile.Design;
+
+namespace DorkNet.AdminMobile.Pages;
+
+public sealed class AdminTabbedPage : TabbedPage
+{
+    public AdminTabbedPage(
+        DashboardPage dashboard,
+        PlayersPage players,
+        RoomsPage rooms,
+        SettingsPage settings)
+    {
+        BarBackgroundColor = AppDesign.Canvas;
+        BarTextColor = AppDesign.Text;
+        SelectedTabColor = AppDesign.PlatformAccent;
+        UnselectedTabColor = AppDesign.Subtle;
+        Children.Add(dashboard);
+        Children.Add(players);
+        Children.Add(rooms);
+        Children.Add(settings);
+    }
+}