[Fix Code Mode] Implement directory processing

[Yiannis128]

ESBMC-AI should be able to process entire directories sequentially. By providing a path to a directory instead of a file, ESBMC-AI should iterate over the files in the entire directory. The output should be saved in the same file as the original file but with an .esbmc-ai.txt.

This will make experimenting with ESBMC-AI way easier and more streamlined.

Should the output be in the form of patches? Perhaps it is worth implementing .patch files. So for main.c, the patch file main.c.patch be created.

TODO

• [Fix Code Mode] Directory Processing Stats Files #104
• Add Directory Processing and Patch Output Generation #140