common: refactor common library pt2 (#8588)

- remove common lib
- split settings, remove common-md
- move ipc interop/kb_layout to interop
- rename core -> settings, settings -> old_settings
- os-detect header-only; interop -> PowerToysInterop
- split notifications, move single-use headers where they're used
- winstore lib
- rename com utils
- rename Updating and Telemetry projects
- rename core -> settings-ui and remove examples folder
- rename settings-ui folder + consisent common/version include

src/settings-ui/Microsoft.PowerToys.Settings.UI/ICoreWindowInterop.cs

@@ -0,0 +1,18 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.InteropServices;
+
+namespace Microsoft.PowerToys.Settings.UI
+{
+    [ComImport]
+    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+    [Guid("45D64A29-A63E-4CB6-B498-5781D298CB4F")]
+    internal interface ICoreWindowInterop
+    {
+        System.IntPtr WindowHandle { get; }
+
+        void MessageHandled(bool value);
+    }
+}