Improve function signatures in API docs of cluster/plot modules

### Location

API docs

### Documentation problem

<img width="1461" height="784" alt="Image" src="https://github.com/user-attachments/assets/808e8b32-a834-4363-a74e-3d1795c766d1" />

Function signatures empty.