Add hscTypecheckRenameWithDiagnostics, for HLS (#24996)

Use runHsc' in runHsc so that both functions can't fall out of sync

We're currently copying parts of GHC code to get structured warnings
in HLS, so that we can recreate `hscTypecheckRenameWithDiagnostics`
locally. Once we get this function into GHC we can drop the copied code
in future versions of HLS.