It’s possible that this caused some files to be corrupted. Although I would be surprised if a suspension also interrupted running PHP processes, they are more likely to be interrupted by script timings (which is why I personally wouldn’t bother with interrupting ongoing requests).
But that doesn’t explain why the entire htdocs folder would be gone. But I doubt it’s a server issue, given that you’re the only one so far who seems to have this issue.
I don’t know why the folder is gone. So I also don’t know if this could happen again.