implement Clean Architecture and user authentication

- Add LoopFit.Domain with entities (ApplicationUser, Workout, CalorieEntry, VitalData), enums (WorkoutType), and interfaces (IJwtTokenGenerator, IUserRepository, IWorkoutRepository)
- Add LoopFit.Application with auth DTOs, service interfaces, and DI setup
- Add LoopFit.Infrastructure with EF Core DbContext (PostgreSQL), ASP.NET Core Identity, JWT token generation, and repository implementations
- Add AuthController with register/login/me endpoints and JWT Bearer auth
- Add MAUI auth services (AuthService, TokenStorageService) and Login/Register Blazor pages

LoopFit.Web/Components/App.razor

@@ -6,11 +6,11 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
     <base href="/"/>
     <ResourcePreloader/>
-    <link rel="stylesheet" href="_content/LoopFit.Shared/lib/bootstrap/dist/css/bootstrap.min.css"/>
-    <link rel="stylesheet" href="_content/LoopFit.Shared/app.css"/>
+    <link rel="stylesheet" href="lib/bootstrap/dist/css/bootstrap.min.css"/>
+    <link rel="stylesheet" href="app.css"/>
     <link rel="stylesheet" href="LoopFit.Web.styles.css"/>
     <ImportMap/>
-    <link rel="icon" type="image/png" href="_content/LoopFit.Shared/favicon.png"/>
+    <link rel="icon" type="image/png" href="favicon.png"/>
     <HeadOutlet @rendermode="InteractiveServer"/>
 </head>
 
@@ -20,4 +20,4 @@
 <script src="@Assets["_framework/blazor.web.js"]"></script>
 </body>
 
-</html>
+</html>