Add integration test for restore of file-based programs

[RikkiGibson]

Depends on changes in dotnet/roslyn#79669

[RikkiGibson]

I gotta say, I am not the most thrilled about certain aspects of javascript debugging. (when the "current statement" being debugged is a whole screenful and then some..)

[dibarbet]

I gotta say, I am not the most thrilled about certain aspects of javascript debugging. (when the "current statement" being debugged is a whole screenful and then some..)

Depending on what you are debugging that may be expected or not. If you are debugging the extension code running in the tests, there should be source maps which let you step through the typescript. But if you're debugging VSCode itself, unfortunately thats what we have without a lot more setup.