Add Explorer Workbench with hierarchical, off-UI Storage analysis.

Storage queries run in the background with cancellation and covering indexes so switching views no longer freezes the UI.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/Explorer.Domain/NameNormalizer.cs

@@ -0,0 +1,34 @@
+using System.Globalization;
+using System.Text;
+
+namespace Explorer.Domain;
+
+public static class NameNormalizer
+{
+    public static string Normalize(string name)
+    {
+        if (string.IsNullOrEmpty(name))
+        {
+            return string.Empty;
+        }
+
+        var form = name.Normalize(NormalizationForm.FormC);
+        return form.ToLower(CultureInfo.InvariantCulture);
+    }
+
+    public static string? Extension(string name)
+    {
+        if (string.IsNullOrEmpty(name))
+        {
+            return null;
+        }
+
+        var idx = name.LastIndexOf('.');
+        if (idx <= 0 || idx == name.Length - 1)
+        {
+            return null;
+        }
+
+        return Normalize(name[(idx + 1)..]);
+    }
+}