Add simulation metadata

[rtimms]

The model, parameterization and how they were simulated are intimately connected. For example, how many mesh points did I need in my model to achieve convergence or the desired accuracy? We should add some simulation metadata so that people providing a BPX can say "I tested this model on this platform using this approach and it worked". Obviously, users are free to use a different platform, but this is useful (and sometimes necessary information)

Things like how the model should be discretised in space (method, gridpoints, etc.) and solver settings.

[ikorotkin]

Please take a look at a suggestion in the discussions.