Integrate DevExpress Web Dashboard into API and Blazor

Added DevExpress Dashboard to ASP.NET Core API and both Blazor WASM/Server frontends. Configured dashboard storage, sample data source, and API endpoint. Updated Blazor projects with dashboard packages, styles, and a new dashboard page. Navigation and configuration updated to support dashboard integration.

DbFirst.BlazorWebApp/appsettings.Development.json

@@ -4,5 +4,6 @@
       "Default": "Information",
       "Microsoft.AspNetCore": "Warning"
     }
-  }
+  },
+  "ApiBaseUrl": "https://localhost:7204/"
 }