Disable bad address writing interop tests with interpreter

[janvorli]

This change disables all libraries interop tests that try to check that access to non-null invalid address throws access violation or null reference exception when executed using the interpreter.

I've introduced a new PlatformDetection.SupportsDirtyAccessViolations for this purpose that is set for coreclr interpreter and for Mono and WASM too. So I have also removed the pre-existing attribute on these tests that was disabling them on Mono.

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[Copilot]

Pull request overview

This PR disables interop tests that verify access violations are thrown for invalid memory addresses when running under interpreters (CoreCLR interpreter, Mono, or WebAssembly). The change introduces a new PlatformDetection.SupportsDirtyAccessViolations property and replaces [SkipOnMono] attributes with runtime conditional checks.

• Adds detection for CoreCLR interpreter mode via environment variables (DOTNET_Interpreter and DOTNET_InterpMode)
• Introduces SupportsDirtyAccessViolations platform detection property that returns false for Mono, CoreCLR interpreter, and WASM
• Updates test methods to conditionally execute second assertion (with offset parameter) based on the new property

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
src/libraries/Common/tests/TestUtilities/System/PlatformDetection.cs	Adds IsCoreClrInterpreter detection logic and SupportsDirtyAccessViolations property to identify platforms that properly throw access violations for invalid memory accesses
src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ReadWrite/IntPtrTests.cs	Removes [SkipOnMono] attributes and wraps offset-based zero pointer tests in runtime condition checks
src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ReadWrite/Int64Tests.cs	Removes [SkipOnMono] attributes and wraps offset-based zero pointer tests in runtime condition checks; removes trailing blank lines
src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ReadWrite/Int32Tests.cs	Removes [SkipOnMono] attributes and wraps offset-based zero pointer tests in runtime condition checks; removes trailing blank lines
src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ReadWrite/Int16Tests.cs	Removes [SkipOnMono] attributes and wraps offset-based zero pointer tests in runtime condition checks; removes trailing blank lines
src/libraries/System.Runtime.InteropServices/tests/System.Runtime.InteropServices.UnitTests/System/Runtime/InteropServices/Marshal/ReadWrite/ByteTests.cs	Removes [SkipOnMono] attributes and wraps offset-based zero pointer tests in runtime condition checks; removes trailing blank lines