core/log: Remove insane mutex trylocks
interface/thread: ThreadedThing::on_crash() and some server/state crash handling improvements
impl/linux/debug: Attempt to not hang or crash when printing signal backtrace
boot/cmem: Override libc's memory allocation when handling fatal signals in order to avoid memory allocation deadlocks; also initialize freed memory to known patterns to ease debugging
lua_bindings/spatial_update_queue: Fix invalid access of freed memory