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/SaxoniteUnitTestsShared/UnitTests/Data/Bus/SaxArticle_ContentData_Tester.cs

@@ -0,0 +1,41 @@
+using NUnit.Framework;
+using Sarand.Net.Standard.Base.Bus;
+using Saxonite.Net.Standard.Base.Bus;
+
+namespace Saxonite.Net.Core.UnitTests.Data.Bus
+{
+	//=======================================================================
+	[TestFixture]
+	public class SaxArticle_ContentData_Tester
+	{
+		//-------------------------------------------------------------------
+		[Test]
+		public void ContentDataRoundTripsBodyAndImageSegments()
+		{
+			SaxArticle.ContentData content = new SaxArticle.ContentData();
+			content.AddSegment().Body.Html = "<p>Fish &amp; chips</p>";
+			content.AddSegment().Image.ItemImageId = new SysId(123);
+
+			SaxArticle.ContentData restored = SaxArticle.ExtractContent(SaxArticle.GetContentData(content));
+
+			Assert.That(restored.Segments, Has.Count.EqualTo(2));
+			Assert.That(restored.Segments[0].Body.Html, Is.EqualTo("<p>Fish &amp; chips</p>"));
+			Assert.That(SysId.ToLong(restored.Segments[1].Image.ItemImageId), Is.EqualTo(123));
+		}
+
+		//-------------------------------------------------------------------
+		[Test]
+		public void ContentDataOmitsInvalidSegments()
+		{
+			SaxArticle.ContentData content = new SaxArticle.ContentData();
+			content.AddSegment();
+			content.AddSegment().Body.Html = "<p>Valid</p>";
+
+			SaxArticle.ContentData restored = SaxArticle.ExtractContent(SaxArticle.GetContentData(content));
+
+			Assert.That(restored.Segments, Has.Count.EqualTo(1));
+			Assert.That(restored.Segments[0].Body.Html, Is.EqualTo("<p>Valid</p>"));
+		}
+	}
+	//=======================================================================
+}