[java-runtime] Improve native library load diagnostics

[jonathanpeppers]

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Pull Request
title and
description
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• Useful description of why the change is necessary.
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• Unit tests

Description

Native library startup failures currently provide too little information to diagnose corrupt, incomplete, or incorrectly split installations.

Route MonoVM, CoreCLR, and NativeAOT startup library loads through a shared helper. When loading fails, the resulting exception and logcat entry identify the requested library, supported ABIs, extracted native-library state, APK and split contents, and the original linker error. If the library is absent from all inspected locations, the message explains that reinstalling may repair a corrupt installation.

Add an MSBuildDeviceIntegration test which removes the real startup library from CoreCLR and NativeAOT APKs, verifies that it is absent from the package, and asserts the improved diagnostic in logcat.

Testing

• src/java-runtime/java-runtime.csproj builds successfully for all runtime JAR variants.
• The generated NativeAOT Java bootstrap compiles against java_runtime_trimmable.jar.
• The new device test was not run locally because the local .NET for Android SDK was unavailable and the full repository build was skipped.

Fixes #5149

[Copilot]

Pull request overview

This PR improves startup diagnostics when the Android runtime fails to load required native libraries (MonoVM/CoreCLR/NativeAOT), making UnsatisfiedLinkError failures actionable by emitting a detailed logcat message (library name, ABI info, nativeLibraryDir state, APK/split contents, and original linker error). It also adds a device integration test that validates the improved diagnostic output by intentionally removing the startup library from built APKs.

Changes:

• Introduces a shared Java helper (NativeLibraryHelper) to wrap System.loadLibrary() and generate rich diagnostics on failure.
• Routes MonoVM/CoreCLR runtime library loads (and NativeAOT bootstrap load) through the shared helper.
• Adds an MSBuildDeviceIntegration test that removes the expected startup library from APKs and asserts the diagnostic appears in logcat.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/MSBuildDeviceIntegration/Tests/NativeLibraryLoadTests.cs	New device test validating the improved native-library load diagnostic in logcat.
src/Xamarin.Android.Build.Tasks/Resources/NativeAotRuntimeProvider.java	Ensures NativeAOT startup explicitly loads the native library via the shared helper path.
src/Xamarin.Android.Build.Tasks/Resources/JavaInteropRuntime.java	Replaces static library loading with an explicit loadLibrary(Context) that uses NativeLibraryHelper.
src/java-runtime/java/mono/android/NativeLibraryHelper.java	New shared helper that wraps native library loading and builds detailed failure diagnostics.
src/java-runtime/java/mono/android/MonoPackageManager.java	Routes MonoVM startup library loads through NativeLibraryHelper for improved error reporting.
src/java-runtime/java/mono/android/clr/MonoPackageManager.java	Routes CoreCLR startup library load through NativeLibraryHelper for improved error reporting.

Suppressed comments (1)

src/java-runtime/java/mono/android/NativeLibraryHelper.java:124

• ❌ error: appendApkDiagnostics also iterates Build.SUPPORTED_ABIS, which can throw on API < 21 and prevent the diagnostic from being generated. Use the same ABI fallback logic here as well so the error reporting works on older Android versions.

				for (String abi : Build.SUPPORTED_ABIS) {