SvgPreviewControl: Add Background so that white .svg are visible (#25397)

* SvgPreviewControl: Add checkered background so that white .svg are visible

* SvgPreviewControl: Move preview generation logic into own class

* SvgPreviewControl: Add possibility to configure background of svg preview pane via the settings ui

* SvgPreviewControl: Take user configuration into consideration when generating svg preview

* SvgPreviewControl: Do not generate preview file, if the actual size is under the 2mb limiation of WebView2

* SvgPreviewControl: Introduce SvgPreviewColorMode enumeration instead of using magic values

* SvgPreviewControl: Add additional checkered pattern shades

* SvgPreviewControl: Use newly introduced enums as default values

src/modules/previewpane/SvgPreviewHandler/Settings.cs

@@ -0,0 +1,74 @@
+// 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 Microsoft.PowerToys.Settings.UI.Library;
+
+namespace SvgPreviewHandler
+{
+    internal sealed class Settings
+    {
+        private static readonly SettingsUtils ModuleSettings = new SettingsUtils();
+
+        public int ColorMode
+        {
+            get
+            {
+                try
+                {
+                    return ModuleSettings.GetSettings<PowerPreviewSettings>(PowerPreviewSettings.ModuleName).Properties.SvgBackgroundColorMode.Value;
+                }
+                catch (FileNotFoundException)
+                {
+                    return PowerPreviewProperties.DefaultSvgBackgroundColorMode;
+                }
+            }
+        }
+
+        public Color SolidColor
+        {
+            get
+            {
+                try
+                {
+                    var colorString = ModuleSettings.GetSettings<PowerPreviewSettings>(PowerPreviewSettings.ModuleName).Properties.SvgBackgroundSolidColor.Value;
+                    return ColorTranslator.FromHtml(colorString);
+                }
+                catch (FileNotFoundException)
+                {
+                    return ColorTranslator.FromHtml(PowerPreviewProperties.DefaultSvgBackgroundSolidColor);
+                }
+            }
+        }
+
+        public Color ThemeColor
+        {
+            get
+            {
+                if (Common.UI.ThemeManager.GetWindowsBaseColor().ToLowerInvariant() == "dark")
+                {
+                    return ColorTranslator.FromHtml("#1e1e1e");
+                }
+                else
+                {
+                    return Color.White;
+                }
+            }
+        }
+
+        public int CheckeredShade
+        {
+            get
+            {
+                try
+                {
+                    return ModuleSettings.GetSettings<PowerPreviewSettings>(PowerPreviewSettings.ModuleName).Properties.SvgBackgroundCheckeredShade.Value;
+                }
+                catch (FileNotFoundException)
+                {
+                    return PowerPreviewProperties.DefaultSvgBackgroundCheckeredShade;
+                }
+            }
+        }
+    }
+}