[infra] Implement XHarness test discovery/running without the XunitFrontController

[kotlarmilos]

Description

Native AOT doesn't support loading a test assembly from disk. To run the library tests on apple mobile platforms with Native AOT, it is required to implement the XHarness test discovery/running without the XunitFrontController, similar to the ThreadlessXunitRunner in XHarness or SingleFileTestRunner in the runtime.

Repro steps

1. Checkout to the https://github.com/kotlarmilos/runtime/tree/feature/nativeaot-library-tests
2. Run the tests using the command below.

./build.sh -ci -arch arm64 -os ios -s libs.tests -c Release /p:ArchiveTests=true /p:RunSmokeTestsOnly=true /p:DevTeamProvisioning=- /p:BuildTestsOn=local /p:UseNativeAOTRuntime=true /p:RunAOTCompilation=false /p:ContinuousIntegrationBuild=true  /p:BuildDarwinFrameworks=true /bl

Tagging subscribers to this area: @dotnet/runtime-infrastructure
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Issue Details

---

Description

Native AOT doesn't support loading a test assembly from disk. To run the library tests on apple mobile platforms, it is required to implement the XHarness test discovery/running without the XunitFrontController.

Repro steps

1. Checkout to the https://github.com/kotlarmilos/runtime/tree/feature/nativeaot-library-tests
2. Run the tests using the command below.

./build.sh -ci -arch arm64 -os ios -s libs.tests -c Release /p:ArchiveTests=true /p:RunSmokeTestsOnly=true /p:DevTeamProvisioning=- /p:BuildTestsOn=local /p:UseNativeAOTRuntime=true /p:RunAOTCompilation=false /p:ContinuousIntegrationBuild=true  /p:BuildDarwinFrameworks=true /bl

Author:	kotlarmilos
Assignees:	-
Labels:	area-Infrastructure, untriaged, needs-area-label
Milestone:	-

Tagging subscribers to 'os-ios': @steveisok, @akoeplinger, @kotlarmilos
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

Native AOT doesn't support loading a test assembly from disk. To run the library tests on apple mobile platforms, it is required to implement the XHarness test discovery/running without the XunitFrontController.

Repro steps

1. Checkout to the https://github.com/kotlarmilos/runtime/tree/feature/nativeaot-library-tests
2. Run the tests using the command below.

./build.sh -ci -arch arm64 -os ios -s libs.tests -c Release /p:ArchiveTests=true /p:RunSmokeTestsOnly=true /p:DevTeamProvisioning=- /p:BuildTestsOn=local /p:UseNativeAOTRuntime=true /p:RunAOTCompilation=false /p:ContinuousIntegrationBuild=true  /p:BuildDarwinFrameworks=true /bl

Author:	kotlarmilos
Assignees:	-
Labels:	area-Infrastructure, os-ios
Milestone:	-