Return dictionaries of custom objects rather than lists

[danbraunai-apollo]

RibBuildResults currently contains list[Eigenvectors], list[Edges], list[InteractionRotation]. It would be a little nicer for analysis if we instead had dict[str, object] keyed by node_layer name.

This would best be done by avoiding lists everywhere for these objects. To maintain order where used, we either need to:

1. Ensure that the insertion order is the same as the node_layers, or
2. Carry around node_layers everywhere.