Implement reader in C ffs

Pretend AI knows how to use drill rocket (actually has no idea of drilling)

finally hwengine in c links without errors

Script loading via physfs which doesn't work: - Some scripts just refuse to load for no obvious reason - Some scripts load fine when you set BUFSIZE to a large value, like 64k, but don't load with small values Error messages in both cases don't seem to have relation to lua file contents

Call fallers less often. Should hopefully still be about as effective at the intended purpose. Should help loads quite a bit.

cmake linking for engine in c

Engine loads fine with basic config

make stats-only mode work headless. also skip a few things to save time/memory.

merge xymeng's gsoc engine with a few updates (and further checks on symbol definitions)

Get rid of Pathz and UserPathz