High-Level Diagrams of SomaticSeq's codebase

[ivanmilevtues]

This PR adds onboarding documents with Mermaid diagrams that provide a high-level overview of the SomaticSeq codebase. You can see an example of how these diagrams render in another project here:
https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main/somaticseq/on_boarding.md

The goal is to help new contributors—especially those who use code as a tool rather than working as full-time software engineers—quickly understand the structure and flow of the code. Given that BioInform is part of Roche, we imagine there are many scientists who interact with code, and we’d love to know if diagrams like these could support their workflows.

We’re curious if this would be helpful for your team, what your current onboarding process looks like, and whether automated diagrams like this could play a role in it.

We generate them using static analysis and LLMs, and we’re building a GitHub Action to keep them updated automatically (e.g., on each merge to main or release).

Full disclosure: We’re in the early stages of building a startup around this, and trying to understand what’s genuinely useful to research and open-source communities.

Thanks so much for taking a look—any feedback would be hugely appreciated!