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/SaxoniteCoreWebOnline/Views/Common/CodeSelect.cshtml

@@ -0,0 +1,59 @@
+@model SaxModel_Online
+@inject SaxLocaliser Localiser
+@{
+	/* Online Code Select */
+	// Ensure view is only included once in page.
+	if (!Model.RegisterView(ViewContext)) return;
+	// Scripts.
+	Model.AdditionalFiles_JS.Add("js/sax-code-sel.js");
+}
+
+<link rel="stylesheet" href="~/css/sax-code-sel.css?@Model.HrefVersion" />
+<div id="dlgCodeSelect" class="sax-dialog sax-form" style="padding-bottom:8px;">
+
+	@* Filter *@
+	<div class=""></div>
+
+	<div class="row h-100">
+
+		@* Available codes *@
+		<div class="col-sm-5">
+
+			<div class="h-100 sax-codeSelect-codes AvailableCodes"></div>
+
+		</div>
+
+		@* Code selection *@
+		<div class="col-sm-2">
+
+			<div class="row">
+
+				<div class="col-sx-6 col-sm-12 center">
+					<button class="sax-button Select">@Localiser["label.select"]</button>
+				</div>
+
+				<div class="col-sx-6 col-sm-12 center">
+					<button class="sax-button Remove">@Localiser["label.remove"]</button>
+				</div>
+
+			</div>
+
+		</div>
+
+		@* Selected codes *@
+		<div class="col-sm-5">
+
+			<div class="h-100 sax-codeSelect-codes SelectedCodes">
+
+			</div>
+		</div>
+
+	</div>
+
+	<div class="sax-panel-item-template">
+		<div class="sax-panel-item Code">
+			<div class="CodeDesc"></div>
+		</div>
+	</div>
+
+</div>