Feature request: enable StoreProtocol.load() to have optional kwargs

[mpvanderschelling]

Some loading methods for custom objects do require other arguments than a self.path in order to be loaded into memory. One example is an equinox.Module with equinox.tree_deserialise_leaves(path_or_file: Union[str, pathlib.Path, BinaryIO], like: PyTree,), which requires a template of the equinox.Module class. Loading this object is not possible in the current state of f3dasm