MTP command-line validation should include the whole command used for running #6194
Description
When running MTP application with invalid arguments, the error message doesn't have the full details as it assumes the user knows and sees the command being invoked. This is not always the case. For example, in dotnet/sdk#49936, I hit a test failure that look like:
[xUnit.net 00:00:33.69] Executing 'dotnet test':
[xUnit.net 00:00:33.69] 》/private/tmp/helix/working/96A40867/t/dotnetSdkTests.SBj8nRNv/c61ab743-cbc5---2915FCD2/bin/Debug/net10.0/TestProject.dll (net10.0|) failed (0ms)
[xUnit.net 00:00:33.69] 》Exit code: 5
[xUnit.net 00:00:33.69] 》 Standard output: Microsoft.Testing.Platform v1.8.0-preview.25374.11+f1ea405d39 (UTC 7/25/2025) [osx-x64 - net10.0]
[xUnit.net 00:00:33.69] 》 Option '--dotnet-test-pipe' from provider 'Platform command line provider' (UID: PlatformCommandLineProvider) expects at most 1 arguments
The error message that MTP produces is not very helpful.