Improve parameters IO for graph ODE-based models

[MaxBetzDLR]

Motivation / Current Behaviour

Parameter_IO for scenarios of germany using a graph has a lot of unwanted dependencies and differes in structure between the different models. Goal is to simplify the structure and make it less dependent on the specific graph, thus improving the readability of code and more expandable in the future. Additionally, we want to add support for creating those graphs with AD types.

Enhancement description

• Rework current structure to be more flexible and support AD types
• Add Graph constructors for simpler instatioation of different type of scenarios
• Broader use of namespace "mio::region::de" for code specific for scenarios of germany

Checklist

• Attached labels, especially loc:: or model:: labels.
• Linked to project