[OOBE]Add What's New page - SCOOBE (#16478)

* [Oobe]Add a What's New page

* Show What's New when version changes

* Add link to GitHub

* Use generic icon for now

* Get only the latest 5 releases

* fix spellchecker

* rename last_version_run.json

* Remove UserControl_Loaded

* Remove installer hash from the release notes

* constexpr some strings

* Add check your internet connection message

src/settings-ui/Settings.UI/OOBE/Views/OobeWhatsNew.xaml

@@ -0,0 +1,52 @@
+<Page x:Class="Microsoft.PowerToys.Settings.UI.OOBE.Views.OobeWhatsNew"
+      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+      xmlns:local="using:Microsoft.PowerToys.Settings.UI.OOBE.Views"
+      xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+      xmlns:controls="using:Microsoft.PowerToys.Settings.UI.Controls"
+      xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
+      xmlns:toolkitcontrols="using:Microsoft.Toolkit.Uwp.UI.Controls"
+      mc:Ignorable="d"
+      Loaded="Page_Loaded">
+    <ScrollViewer
+        VerticalScrollBarVisibility="Auto"
+        Padding="32,24,32,24">
+
+        <StackPanel
+            Orientation="Vertical"
+            VerticalAlignment="Top">
+
+            <TextBlock
+                x:Name="TitleTxt"
+                Text=""
+                AutomationProperties.HeadingLevel="Level1"
+                Style="{StaticResource TitleTextBlockStyle}" />
+            <HyperlinkButton
+                NavigateUri="https://github.com/microsoft/PowerToys/releases"
+                Margin="0,0,0,16"
+                Style="{StaticResource TextButtonStyle}">
+                <TextBlock
+                    x:Uid="Oobe_WhatsNew_DetailedReleaseNotesLink"
+                    TextWrapping="Wrap" />
+            </HyperlinkButton>
+            <muxc:ProgressRing
+                x:Name="LoadingProgressRing"
+                IsIndeterminate="True"
+                Visibility="Visible"/>
+            <muxc:InfoBar
+                Severity="Error"
+                x:Name="ErrorInfoBar"
+                x:Uid="Oobe_WhatsNew_LoadingError"
+                Visibility="Collapsed"
+                IsClosable="False"
+                IsOpen="True"
+                IsTabStop="True" />
+            <toolkitcontrols:MarkdownTextBlock
+                x:Name="ReleaseNotesMarkdown"
+                Visibility="Collapsed"
+                Background="Transparent"
+                LinkClicked="ReleaseNotesMarkdown_LinkClicked"/>
+        </StackPanel>
+    </ScrollViewer>
+</Page>