[com1]: Compute erosion and deposition rates

[PaulaSp3]

for few first ideas see: https://hedgedoc.avaframe.org/Lxl4uOukR1OHeE0UR_bF9Q?both

further literature:

• https://nhess.copernicus.org/articles/16/2325/2016/
• https://doi.org/10.1017/aog.2024.10