Harden application artifact extension ordering

Make Build a mandatory GetApplicationArtifacts dependency instead of part of the overridable GetApplicationArtifactsDependsOn property. Extension targets still run after platform artifacts are produced, and tests now overwrite the property to prove Build cannot be removed while metadata augmentation still applies to GetApplicationArtifacts and Publish.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Redth

docs/building-apps/build-properties.md

@@ -545,7 +545,8 @@ Where the generated source from the generator are saved.
 
 A semi-colon delimited property that can be used to extend the
 [GetApplicationArtifacts](build-targets.md#getapplicationartifacts) and
-`Publish` targets. MSBuild targets added to this property will execute after
+`Publish` targets. The platform build is a mandatory dependency of
+`GetApplicationArtifacts`; MSBuild targets added to this property execute after
 the platform build has collected `@(ApplicationArtifact)` items and before
 `GetApplicationArtifacts` or `Publish` returns them.
 

docs/building-apps/build-targets.md

@@ -47,9 +47,10 @@ Added in .NET 11.
 ## GetApplicationArtifacts
 
 Builds the project and returns the `@(ApplicationArtifact)` item group. This
-target can be used by custom build scripts to query final `.app`, `.ipa`,
-`.pkg`, and `.xcarchive` artifacts. The `Publish` target returns the same item
-group for artifacts it creates.
+target always runs the platform build first so `.app`, `.ipa`, `.pkg`, and
+`.xcarchive` artifacts are populated before any custom metadata extension
+targets run. The `Publish` target returns the same item group for artifacts it
+creates.
 
 ```shell
 $ dotnet build -t:GetApplicationArtifacts

msbuild/Xamarin.Shared/Xamarin.Shared.targets

@@ -3429,17 +3429,13 @@ Copyright (C) 2018 Microsoft. All rights reserved.
 			_ZipIpa
 		</CreateIpaDependsOn>
 
-		<GetApplicationArtifactsDependsOn>
-			Build;
-			$(GetApplicationArtifactsDependsOn)
-		</GetApplicationArtifactsDependsOn>
 	</PropertyGroup>
 
 	<Target Name="_BeforeCreateIpaForDistribution" Condition="'$(IsAppDistribution)' == 'true'" DependsOnTargets="$(_BeforeCreateIpaForDistributionDependsOn)" />
 
 	<Target Name="CreateIpa" Condition="'$(_CanArchive)' == 'true' And '$(SdkIsDesktop)' != 'true'" DependsOnTargets="$(CreateIpaDependsOn)" />
 
-	<Target Name="GetApplicationArtifacts" DependsOnTargets="$(GetApplicationArtifactsDependsOn)" Returns="@(ApplicationArtifact)" />
+	<Target Name="GetApplicationArtifacts" DependsOnTargets="Build;$(GetApplicationArtifactsDependsOn)" Returns="@(ApplicationArtifact)" />
 
 	<Import Project="$(MSBuildThisFileDirectory)Xamarin.Shared.ObjCBinding.targets" Condition="'$(IsBindingProject)' == 'true'" />
 

tests/dotnet/UnitTests/PostBuildTest.cs

@@ -117,7 +117,7 @@ public void GetApplicationArtifactsDependsOnTest (ApplePlatform platform, string
 			var existingProjectContent = File.ReadAllText (project_path);
 			var newProjectContent = existingProjectContent.Replace ("</Project>", @"
 	<PropertyGroup>
-		<GetApplicationArtifactsDependsOn>$(GetApplicationArtifactsDependsOn);AddMauiApplicationArtifactMetadata</GetApplicationArtifactsDependsOn>
+		<GetApplicationArtifactsDependsOn>AddMauiApplicationArtifactMetadata</GetApplicationArtifactsDependsOn>
 	</PropertyGroup>
 	<Target Name=""AddMauiApplicationArtifactMetadata"">
 		<ItemGroup>
@@ -325,7 +325,7 @@ public void PublishApplicationArtifactsDependsOnTest (ApplePlatform platform, st
 			var existingProjectContent = File.ReadAllText (project_path);
 			var newProjectContent = existingProjectContent.Replace ("</Project>", @"
 	<PropertyGroup>
-		<GetApplicationArtifactsDependsOn>$(GetApplicationArtifactsDependsOn);AddMauiPublishApplicationArtifactMetadata</GetApplicationArtifactsDependsOn>
+		<GetApplicationArtifactsDependsOn>AddMauiPublishApplicationArtifactMetadata</GetApplicationArtifactsDependsOn>
 	</PropertyGroup>
 	<Target Name=""AddMauiPublishApplicationArtifactMetadata"">
 		<ItemGroup>