Remove unused using directives from API and client files

Cleaned up unnecessary System.Net and System.Net.Http.Json usings across multiple files, including controllers and API client classes, to reduce dependencies and improve code clarity.

DbFirst.API/Controllers/CatalogsController.cs

@@ -1,7 +1,6 @@
 using DbFirst.Application.Catalogs;
 using DbFirst.Application.Catalogs.Commands;
 using DbFirst.Application.Catalogs.Queries;
-using DbFirst.Domain;
 using MediatR;
 using Microsoft.AspNetCore.Mvc;
 

DbFirst.BlazorWebApp/Services/ApiClientHelper.cs

@@ -1,5 +1,4 @@
 using System.Net;
-using System.Net.Http.Json;
 
 namespace DbFirst.BlazorWebApp.Services;
 

DbFirst.BlazorWebApp/Services/CatalogApiClient.cs

@@ -1,5 +1,3 @@
-using System.Net;
-using System.Net.Http.Json;
 using DbFirst.BlazorWebApp.Models;
 
 namespace DbFirst.BlazorWebApp.Services;

DbFirst.BlazorWebApp/Services/DashboardApiClient.cs

@@ -1,4 +1,3 @@
-using System.Net.Http.Json;
 using DbFirst.BlazorWebApp.Models;
 
 namespace DbFirst.BlazorWebApp.Services;

DbFirst.BlazorWebApp/Services/LayoutApiClient.cs

@@ -1,4 +1,3 @@
-using System.Net.Http.Json;
 using DbFirst.BlazorWebApp.Models;
 
 namespace DbFirst.BlazorWebApp.Services;

DbFirst.BlazorWebApp/Services/MassDataApiClient.cs

@@ -1,4 +1,3 @@
-using System.Net.Http.Json;
 using DbFirst.BlazorWebApp.Models;
 
 namespace DbFirst.BlazorWebApp.Services;