Reworking the filequeue, the buffer chaining logic and the error handling. Renaming functions. Fix bug in arena.
Small improvements of the LF MPMC queue Making the LF MPMC queue generic and in a seperate header file
Instead of writing directly to file_hashes.txt, hash_workers now are using a local arena, writing everything once at the end using #pragma once to ensure that a given header file is included only once in a single compilation unit
