v1.3.0 Restructure Saxonite workspace and upgrade to .NET 10 (#1)

Move Saxonite’s projects into a dedicated `Workspace` folder and align the solution with .NET 10 and the current Common workspace. Update encryption integration, test project structure and coverage, and repository guidance and upgrade notes.

- Relocate application and library projects while retaining Git rename history.
- Split tests into Admin, Online, and Shared projects; add representative behavioral and serialization tests.
- Update Common integration, application version, and repository documentation.

Application version: 1.3.0

Reviewed-on: #1
Co-authored-by: andy <andy@sarand.com>

Workspace/SaxoniteCoreWeb/Base/Middleware/SaxMetadataProvider.cs

@@ -0,0 +1,23 @@
+using Microsoft.AspNetCore.Mvc.ModelBinding.Metadata;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Saxonite.Net.Core.Web.Base.Middleware
+{
+	//=======================================================================
+	/// <summary>
+	/// Force blank form values to be populated to the model as empty strings rather than null values.
+	/// </summary>
+	public class SaxMetadataProvider : IMetadataDetailsProvider, IDisplayMetadataProvider
+	{
+		public void CreateDisplayMetadata(DisplayMetadataProviderContext context)
+		{
+			if (context.Key.MetadataKind == ModelMetadataKind.Property)
+			{
+				context.DisplayMetadata.ConvertEmptyStringToNull = false;
+			}
+		}
+	}
+	//=======================================================================
+}