breaking: Add .NET 10 Support and Upgrade to ReactiveUI 22.0 (#834)

* Initial plan

* Complete Directory.Build.props migration and project updates

- Unshallowed git repository
- Installed .NET 10 SDK
- Renamed Directory.build.props to Directory.Build.props (case-sensitive)
- Renamed Directory.build.targets to Directory.Build.targets
- Updated Directory.Build.props with new target framework definitions
- Updated global.json to allow SDK 10.0
- Updated ReactiveUI.Validation.csproj to use $(LibraryTargetFrameworks)
- Updated ReactiveUI.Validation.Tests.csproj to use $(TestTargetFrameworks)
- Added net10.0 API approval test verification file
- Suppressed pre-existing StyleCop warnings in test project
- All builds and tests passing for net8.0, net9.0, and net10.0

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Fix StyleCop errors and update NuGet packages

- Removed SA1600, SA1513, SA1028, RCS1037 from NoWarn suppressions
- Added documentation for SetUp and TearDown methods
- Fixed trailing whitespace in PropertyValidationTests.cs
- Added blank lines after closing braces per SA1513
- Updated NuGet packages:
  - Nerdbank.GitVersioning: 3.7.115 → 3.8.118
  - Roslynator.Analyzers: 4.14.0 → 4.14.1
  - System.Collections.Immutable: 9.0.8 → 9.0.9
  - Microsoft.NET.Test.Sdk: 17.14.1 → 18.0.0
  - Microsoft.Reactive.Testing: 6.0.2 → 6.1.0
- Kept ReactiveUI at 21.0.1 (22.0.1 introduces breaking changes)
- All tests passing

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Update AndroidX project to use MauiAndroidTargets variable and remove net8.0-android

- Updated ReactiveUI.Validation.AndroidX.csproj to use $(MauiAndroidTargets) variable
- Removed deprecated net8.0-android target (Microsoft deprecated)
- Now targets net9.0-android and net10.0-android only
- Kept ReactiveUI packages at 21.0.1 (22.0.1 has breaking changes)
- AndroidX project builds successfully
- All tests passing

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Update ReactiveUI to 22.0.1 with System.Reactive.Disposables.Fluent namespace

- Upgraded ReactiveUI from 21.0.1 to 22.0.1
- Upgraded ReactiveUI.AndroidX from 21.0.1 to 22.0.1
- Added using System.Reactive.Disposables.Fluent directive to files using DisposeWith
- DisposeWith extension method moved from ReactiveUI to System.Reactive.Disposables.Fluent namespace
- All tests passing (68 tests across net8.0, net9.0, net10.0)

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Add .NET 10 Support and Upgrade to ReactiveUI 22.0

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Remove NoWarn from test project and fix non-nullable field initializations

- Removed NoWarn line completely from test project csproj
- Fixed all CS8618 errors (non-nullable field must contain non-null value) by adding = null! to 156 fields/properties in Model classes
- Test project now has nullable reference types enabled
- Remaining: CS8602, CS8600, CS8625, CS8604 errors in test methods (114 errors total)
- All Model classes now properly initialize non-nullable members with null!

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Remove redundant global.json file

- Removed global.json as it's no longer needed
- SDK version management handled by build environment
- Simplifies repository configuration

Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

* Further fixes

* Fixes

* Fix warnings

* Fix api warnings

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: glennawatson <5834289+glennawatson@users.noreply.github.com>

Author: Copilot

global.json

@@ -1,11 +1,15 @@
-<Project>  
+<Project>
   <PropertyGroup>
-    <Copyright>Copyright (c) .NET Foundation and Contributors</Copyright>
+    <EnableWindowsTargeting>true</EnableWindowsTargeting>
+    <WarningsAsErrors>$(WarningsAsErrors);nullable</WarningsAsErrors>
+    <LangVersion>preview</LangVersion>
+    <Nullable>enable</Nullable>
+    <Copyright>Copyright © 2019-$(CompanyName) $([System.DateTime]::Now.ToString(`yyyy`)) ReactiveUI and Contributors</Copyright>
     <Product>ReactiveUI.Validations ($(TargetFramework))</Product>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
     <PackageProjectUrl>https://github.com/reactiveui/ReactiveUI.Validation/</PackageProjectUrl>
     <PackageIconUrl>https://github.com/reactiveui/ReactiveUI.Validation/blob/master/media/logo.png?raw=true</PackageIconUrl>
-    <Authors>.NET Foundation and Contributors</Authors>
+    <Authors>ReactiveUI and Contributors</Authors>
     <Description>Validations library for ReactiveUI.</Description>
     <Owners>xanaisbettsx;ghuntley</Owners>
     <PackageTags>reactiveui;validation library;reactive programming;netcore;netstandard;netframework</PackageTags>
@@ -24,12 +28,28 @@
     <!-- Optional: Include PDB in the built .nupkg -->
     <AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>
     <WarningsAsErrors>CS8600;CS8602;CS8603;CS8604;CS8605;CS8606;CS8607;CS8608;CS8609;CS8610;CS8611;CS8612;CS8613;CS8614;CS8615;CS8616;CS8617;CS8618;CS8619;CS8620;CS8621;CS8622;CS8623;CS8624;CS8625</WarningsAsErrors>
-    <LangVersion>preview</LangVersion>
     <EnableNETAnalyzers>True</EnableNETAnalyzers>
     <AnalysisLevel>latest</AnalysisLevel>
-		<NoWarn>$(NoWarn);IDE1006;IDE0130</NoWarn>
+    <NoWarn>$(NoWarn);IDE1006;IDE0130</NoWarn>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <NetCorePlatforms>net8.0;net9.0;net10.0;netstandard2.0</NetCorePlatforms>
+    <NetWindowsPlatforms>net8.0-windows10.0.19041.0;net9.0-windows10.0.19041.0;net10.0-windows10.0.19041.0</NetWindowsPlatforms>
+    <MauiAndroidTargets>net9.0-android;net10.0-android</MauiAndroidTargets>
+    <MauiAppleTargets>net9.0-ios;net9.0-tvos;net9.0-macos;net9.0-maccatalyst;net10.0-ios;net10.0-tvos;net10.0-macos;net10.0-maccatalyst</MauiAppleTargets>
+    <NetFrameworkPlatforms Condition="$([MSBuild]::IsOSPlatform('Windows'))">net462;net472</NetFrameworkPlatforms>
+    <TestTargetFrameworks>net8.0;net9.0;net10.0</TestTargetFrameworks>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <CreatableMauiTargets Condition="$([MSBuild]::IsOSPlatform('Windows'))">$(MauiAndroidTargets);$(MauiAppleTargets)</CreatableMauiTargets>
+    <CreatableMauiTargets Condition="$([MSBuild]::IsOSPlatform('OSX'))">$(MauiAndroidTargets);$(MauiAppleTargets)</CreatableMauiTargets>
+    <CreatableMauiTargets Condition="$([MSBuild]::IsOSPlatform('Linux'))">$(MauiAndroidTargets)</CreatableMauiTargets>
+
+    <LibraryTargetFrameworks>$(NetCorePlatforms);$(NetWindowsPlatforms);$(CreatableMauiTargets);$(NetFrameworkPlatforms)</LibraryTargetFrameworks>
+  </PropertyGroup>
+  
   <ItemGroup>
     <None Include="$(MSBuildThisFileDirectory)..\media\logo.png" Pack="true" PackagePath="\" />
     <None Include="$(MSBuildThisFileDirectory)..\LICENSE" Pack="true" PackagePath="LICENSE" />
@@ -40,9 +60,9 @@
 		<PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
 	</ItemGroup>
 	<ItemGroup>
-		<PackageReference Include="Nerdbank.GitVersioning" Version="3.7.115" PrivateAssets="all" />
+		<PackageReference Include="Nerdbank.GitVersioning" Version="3.8.118" PrivateAssets="all" />
 		<PackageReference Include="stylecop.analyzers" Version="1.2.0-beta.556" PrivateAssets="all" />
-		<PackageReference Include="Roslynator.Analyzers" Version="4.14.0" PrivateAssets="All" />
+		<PackageReference Include="Roslynator.Analyzers" Version="4.14.1" PrivateAssets="All" />
 	</ItemGroup>
 	<ItemGroup>
 		<AdditionalFiles Include="$(MSBuildThisFileDirectory)stylecop.json" Link="stylecop.json" />

src/Directory.build.props src/Directory.Build.propssrc/Directory.build.props renamed to src/Directory.Build.props

@@ -1,6 +1,6 @@
-// Copyright (c) 2025 .NET Foundation and Contributors. All rights reserved.
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
+// Copyright (c) 2025 ReactiveUI and Contributors. All rights reserved.
+// Licensed to the ReactiveUI and Contributors under one or more agreements.
+// The ReactiveUI and Contributors licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
 using System;

src/Directory.build.targets src/Directory.Build.targetssrc/Directory.build.targets renamed to src/Directory.Build.targets

@@ -1,15 +1,16 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0-android;net9.0-android</TargetFrameworks>
+    <TargetFrameworks>$(MauiAndroidTargets)</TargetFrameworks>
     <PackageDescription>Provides ReactiveUI.Validation extensions for the AndroidX Library</PackageDescription>
     <PackageId>ReactiveUI.Validation.AndroidX</PackageId>
     <NoWarn>$(NoWarn);CS1591</NoWarn>
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="ReactiveUI.AndroidX" Version="21.0.1" />
+    <PackageReference Include="ReactiveUI.AndroidX" Version="22.0.1" />
+    <PackageReference Include="Xamarin.Google.Android.Material" Version="1.12.0.5" />
   </ItemGroup>
 
   <ItemGroup>