[FileExplorer]Add QoiThumbnailProvider and QoiPreviewHandler (#29735)

* [FileExplorer]QoiThumbnailProvider

* Corrects code documentation

* Adds QoiPreviewHandler

* Corrects GUIDs

* Ensure returned thumbnail image is 32bit ARGB

* Updates following review comments

* More updates following review comments

* Updates following PR comments

* Fix dark theme background in QoiPreviewHandler

* Updates attribution text

src/modules/previewpane/UnitTests-QoiThumbnailProvider/QoiThumbnailProviderTests.cs

@@ -0,0 +1,61 @@
+// 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.Drawing;
+using Microsoft.PowerToys.STATestExtension;
+using Microsoft.PowerToys.ThumbnailHandler.Qoi;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace QoiThumbnailProviderUnitTests
+{
+    [STATestClass]
+    public class QoiThumbnailProviderTests
+    {
+        [TestMethod]
+        public void GetThumbnailValidStreamQoi()
+        {
+            // Act
+            var filePath = "HelperFiles/sample.qoi";
+
+            QoiThumbnailProvider provider = new QoiThumbnailProvider(filePath);
+
+            Bitmap bitmap = provider.GetThumbnail(256);
+
+            Assert.IsTrue(bitmap != null);
+        }
+
+        [TestMethod]
+        public void GetThumbnailInValidSizeQoi()
+        {
+            // Act
+            var filePath = "HelperFiles/sample.qoi";
+
+            QoiThumbnailProvider provider = new QoiThumbnailProvider(filePath);
+
+            Bitmap bitmap = provider.GetThumbnail(0);
+
+            Assert.IsTrue(bitmap == null);
+        }
+
+        [TestMethod]
+        public void GetThumbnailToBigQoi()
+        {
+            // Act
+            var filePath = "HelperFiles/sample.qoi";
+
+            QoiThumbnailProvider provider = new QoiThumbnailProvider(filePath);
+
+            Bitmap bitmap = provider.GetThumbnail(10001);
+
+            Assert.IsTrue(bitmap == null);
+        }
+
+        [TestMethod]
+        public void CheckNoQoiNullStringShouldReturnNullBitmap()
+        {
+            Bitmap thumbnail = QoiThumbnailProvider.GetThumbnail(null, 256);
+            Assert.IsTrue(thumbnail == null);
+        }
+    }
+}