De-Slopping a rust codebase?

Hello, random Redditors, I'm looking for opinions on best practices for de-slopping a codebase if anyone's tried this yet. For context, I was working on it for two years, and about 6 months ago started vibe coding in it. It's not that the overall architecture changed much, or that I'm not happy with features Claude added; it's just that so much of the code I look at and don't recognize or fully understand anymore, and it's very much a code that I would need to fully understand before I tried using it for sharing it/standing behind it (its the core particle based communication and neighboring of LAMMPS written in rust if you know what that is)

Do I make a spreadsheet and go through every line of code? Just the key important stuff? Rewrite it from scratch?