[Feature request]: refactor model_info

[pearsonca]

Label

config, meta/workflow

Priority Label

low priority

Is your feature request related to a problem? Please describe.

Part of the too-tightly coupled nature of flepimop internals.

Is your feature request related to a new application, scenario round, pathogen? Please describe.

No response

Describe the solution you'd like

As written, ModelInfo objects know how to write themselves to a specific place. This means that their signature includes lots of arguments that have nothing to do with their core purpose. This also means that their construction arguments are fundamentally entangling with their pickling arguments - that means that if you wanted to, e.g., write whatever ModelInfo's yield to two different places, you'd have to construct two different instances.

I get the instinct here - definitely need some kind of friend pattern. But it makes more sense to have all this file handling / formatting as its own encapsulated capability.