Removing WCT 7.x references (#41733)

## Summary of the Pull Request

This PR introduces the following changes:
- Replace the MarkdownTextBlock with the latest version in
CommunityToolkit Labs, and removing the 7.x version.
- Replacing WrapPanel from 7.x with the 8.0 version.
- Replacing converters from 7.x with the 8.0 version.
- Remove unused namespaces related to the Toolkit

No visual or behavior changes, except for the release notes that now
look better :):

Before:
<img width="678" height="906" alt="image"
src="https://github.com/user-attachments/assets/8b3ac267-b4cd-499c-8e16-d8420a176a4a"
/>


After:
<img width="846" height="881" alt="image"
src="https://github.com/user-attachments/assets/cb4f2d85-0c23-4263-80d6-28c2ab403704"
/>


<!-- Please review the items on the PR checklist before submitting-->
## PR Checklist

- [ ] Closes: #xxx
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

---------

Co-authored-by: Gordon Lam <73506701+yeelam-gordon@users.noreply.github.com>
Co-authored-by: Gordon Lam (SH) <yeelam@microsoft.com>

src/settings-ui/Settings.UI/SettingsXAML/Views/AwakePage.xaml.cs

@@ -5,14 +5,12 @@
 using System;
 using System.IO;
 using System.IO.Abstractions;
-
 using ManagedCommon;
 using Microsoft.PowerToys.Settings.UI.Helpers;
 using Microsoft.PowerToys.Settings.UI.Library;
 using Microsoft.PowerToys.Settings.UI.Library.Interfaces;
 using Microsoft.PowerToys.Settings.UI.ViewModels;
 using Microsoft.UI.Dispatching;
-using Microsoft.UI.Xaml.Controls;
 using PowerToys.GPOWrapper;
 
 namespace Microsoft.PowerToys.Settings.UI.Views

src/settings-ui/Settings.UI/SettingsXAML/Views/ImageResizerPage.xaml

@@ -9,7 +9,7 @@
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:models="using:Microsoft.PowerToys.Settings.UI.Library"
     xmlns:tkcontrols="using:CommunityToolkit.WinUI.Controls"
-    xmlns:toolkitconverters="using:CommunityToolkit.WinUI.UI.Converters"
+    xmlns:tkconverters="using:CommunityToolkit.WinUI.Converters"
     xmlns:ui="using:CommunityToolkit.WinUI"
     x:Name="RootPage"
     AutomationProperties.LandmarkType="Main"
@@ -23,7 +23,7 @@
         <converters:ImageResizerDoubleToAutoConverter x:Key="ImageResizerDoubleToAutoConverter" />
         <converters:ImageResizerNumberBoxValueConverter x:Key="ImageResizerNumberBoxValueConverter" />
         <converters:ImageResizerZeroToEmptyStringNumberFormatter x:Key="ImageResizerZeroToEmptyStringNumberFormatter" />
-        <toolkitconverters:BoolToObjectConverter
+        <tkconverters:BoolToObjectConverter
             x:Key="BoolToComboBoxIndexConverter"
             FalseValue="1"
             TrueValue="0" />

src/settings-ui/Settings.UI/SettingsXAML/Views/MouseWithoutBordersPage.xaml

@@ -3,17 +3,17 @@
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:controls="using:Microsoft.PowerToys.Settings.UI.Controls"
-    xmlns:converters="using:CommunityToolkit.WinUI.UI.Converters"
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
     xmlns:local="using:Microsoft.PowerToys.Settings.UI.Helpers"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:tkcontrols="using:CommunityToolkit.WinUI.Controls"
+    xmlns:tkconverters="using:CommunityToolkit.WinUI.Converters"
     xmlns:ui="using:CommunityToolkit.WinUI"
     AutomationProperties.LandmarkType="Main"
     mc:Ignorable="d">
     <local:NavigablePage.Resources>
-        <converters:BoolToVisibilityConverter x:Key="negativeBoolToVisibilityConverter" />
-        <converters:BoolToObjectConverter
+        <tkconverters:BoolToVisibilityConverter x:Key="negativeBoolToVisibilityConverter" />
+        <tkconverters:BoolToObjectConverter
             x:Key="OneRowMatrixBoolToNumberOfRowsConverter"
             FalseValue="2"
             TrueValue="4" />