The MinGW64 build of Qt6 renames 'main' to 'qMain' to ensure its runtime is executed first.
This unfortunately fouls anything else called 'main', so rename the symbol to 'run'.
- Simple implementation of OS list fetching in backend
- Replace frontend OS list fetching by calls to backend
- OS list updates are brought in asynchronously, avoiding excessive UI
blockage.
- "Erase" and "Custom" OS list options are always present, even in a
no-internet scenario
Based-On: cillian64/rpi-imager/oslist_backend
This is a compromised change. Essentially, I'm working around a
poorly-understood failure mode in Qt5, where the disk cache can
occasionally fail to invalidate, resulting in stale compiled units being
used.
This will increase application start times in favour of correctness.
