Refactor namespaces and enhance application structure

This commit reorganizes namespaces from `DigitalData.Core.Abstractions` and `DigitalData.Core.DTO` to `DigitalData.Core.Application.Interfaces` and `DigitalData.Core.Application.DTO`, improving maintainability and clarity.

Updated using directives across multiple files to reflect the new structure, ensuring functionality remains intact.

Project references in `DigitalData.Core.API.csproj` have been consolidated to include the new Application project.

Introduced new classes and interfaces such as `BaseDTO`, `CookieConsentSettings`, `DataResult`, `Notice`, and `Result` to enhance data transfer and service result handling.

Updated `IRepository`, `ICRUDRepository`, and `IEntityMapper` interfaces to facilitate CRUD operations and entity mapping.

Added extension methods in `Extensions.cs` to improve repository usability.

New interfaces for HTTP client services have been added, enhancing external API call handling.

Overall, these changes reflect a significant restructuring aimed at improving organization and preparing for future development.

DigitalData.Core.Client/Interface/IBaseHttpClientService.cs

@@ -0,0 +1,22 @@
+using System.Net;
+
+namespace DigitalData.Core.Client.Interface
+{
+    public interface IBaseHttpClientService
+    {
+        CookieCollection GetCookies(string path = "");
+
+        Task<HttpResponseMessage> FetchAsync(
+            string? scheme = null,
+            int? port = null,
+            string path = "",
+            IEnumerable<KeyValuePair<string, object?>>? queryParams = null,
+            HttpMethod? method = null,
+            HttpContent? body = null,
+            IEnumerable<KeyValuePair<string, object>>? form = null,
+            IEnumerable<KeyValuePair<string, object>>? headers = null,
+            bool sendWithCookie = true,
+            bool saveCookie = true
+        );
+    }
+}