Improve handling corrupted files (Error: [PoolArchive::GetFileImpl] failed to read file)

Sometimes we have a problem when files got corrupt. And this occured problem remain until user manually read own log and delete that file so it's got redownloaded.

There's confirmed cases that it's leads to desyncs.

Start at PoolArchive::GetFileImpl and investigate the corrupted-file read path described in the issue. Reproduce the failure if possible; done should mean corrupted files are handled without requiring manual log inspection and deletion, and confirmed cases no longer cause desyncs.

Written by the indexing model from the issue text.