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/SaxoniteCoreWebAdmin/Views/Common/SelectItem.cshtml

@@ -0,0 +1,53 @@
+@model SaxModel_Admin
+@inject SaxLocaliser Localiser
+@{
+	// Ensure view is only included once in page.
+	if (!Model.RegisterView(ViewContext)) return;
+	// Scripts.
+	Model.AdditionalFiles_JS.Add("js/sax-sel-itm.js");
+}
+
+<link rel="stylesheet" href="~/css/sax-selectItem.css?@Model.HrefVersion" />
+
+<div id="dlgSelectItem" class="sax-dialog sax-form">
+
+	<div class="container-fluid h-100">
+
+		@* Selected Item *@
+		<div class="SelectedItem">
+			<div class="row">
+				<div class="col-sm-12"><div class="sax-label">@Localiser["label.item.selected"]:</div></div>
+				<div class="col-sm-12"><div class="SelectedItemName"></div></div>
+			</div>
+			<div class="spacer2"></div>
+		</div>
+
+		@* Item Filter *@
+		<div class="ItemFilter sax-form">
+			<div class="row">
+				<div class="col right"><div class="sax-label">@Localiser["label.search"]</div></div>
+				<div class="fixed"><input type="search" id="ifItemFilter" class="sax-input" autocomplete="off" onkeyup="sax.data.selectItem.fn.displayItems();" /></div>
+			</div>
+			<div class="spacer2"></div>
+		</div>
+
+		@* Available items *@
+		<div class="row">
+			<div class="col"><div class="sax-label bottom">@Localiser["label.items.available"]:</div></div>
+		</div>
+
+		<div class="row">
+
+			<div class="col-sm-12 sax-selectItem-items AvailableItems"></div>
+
+		</div>
+
+	</div>
+
+	<div class="sax-panel-item-template">
+		<div class="sax-panel-item Item">
+			<div class="ItemName"></div>
+		</div>
+	</div>
+
+</div>