Shared Package Container and AppModel API

TIMOTHY_MANGAN There is an API for that yes SharedPackageContainerManager Class (Windows.Management.Deployment) - Windows UWP applications | Microsoft Learn

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TEST_METHOD(GetContainer)
        {
            auto id = CreatSimpleContainer(L"container", {
                L"family1_8wekyb3d8bbwe",
                L"family2_8wekyb3d8bbwe"
            }).Id();

            auto manager = winrt::SharedPackageContainerManager::GetDefault();
            
            // Get container
            auto container = manager.GetContainer(id);

            log(L"Container name: ", container.Name().c_str());
            log(L"Container id: ", container.Id().c_str());
            VERIFY_ARE_EQUAL(container.Name(),                      L"container");
            VERIFY_ARE_EQUAL(container.Id().size(),                 36u);

            auto members = container.GetMembers();
            VERIFY_ARE_EQUAL(members.Size(), 2u);
            VERIFY_ARE_EQUAL(members.GetAt(0).PackageFamilyName(),  L"family1_8wekyb3d8bbwe");
            VERIFY_ARE_EQUAL(members.GetAt(1).PackageFamilyName(),  L"family2_8wekyb3d8bbwe");
        }