Apparently we'd never bothered opting in, despite nearly everything in all out apps being entirely compatible and designed with long paths in mind.
GetModuleFileNameW is a bit awkward as it's just about the only Win32 function that returns the minimum of the buffer size and the string size - nearly everything else returns the full size even if it won't fit, so you can pass it a null pointer and a size of zero, and it'll tell you how much space you need to allocate.
I pretty much just copied the mostly-working long-path-friendly call site in the crash catcher to windowspath.cpp, but I also noticed that if the function failed and returned zero, the original implementation would loop forever, so I fixed that.
There was some code that could be ditched from the catch monitor as \\?\ is a prefix you can use to opt into long paths for a single API call instead of using the manifest to set it everywhere.
