Idea: Refactoring of the `FieldWrapper` class

[lebrice]

Would be a good idea to refactor the FieldWrapper class a bit. The args_dict (a dict of all the argparse arguments for a given field, that get passed to parser.add_arguments in the FieldWrapper) is currently created using a mix of three things (with increasing priority):

• The type annotation of the field
• The dataclass context (e.g. when adding an Optional[Dataclass] field on another dataclass, or when using the default or prefix arguments to parser.add_arguments, etc.
• The manual overrides (arguments of parser.add_argument passed to the field function)

These three are currently a bit mixed together in the FieldWrapper class. It would perhaps be preferable to have them be cleanly separated.

[idoby]

Yeah, it needs some love. I find it especially limiting that DataclassWrapper/FieldWrapper do too much by themselves and so injecting new information into the process is hard (e.g. creating a feature that has an effect at the field level but is specified as an argument to add_arguments())