[bug] Crash when doing search and replace

mediapathic

This only happened once, and I don't have time to replicate a bunch of test conditions right now, but it was clear from the timing that the crash happened because of the search.

I did a search and replace for ``` {.example} (I have some files that converted from org to md poorly). The replace string was blank. The moment I hit "all", The Archive crashed instantly.

As I say, I apologize for not being able to try to replicate, but I thought it might be useful to look into.