Merge Molstar and AlphaFoldMolstar components

[kamilzyla]

Goal

Have just a single Molstar component which can read the protein data from different sources depending on what prop is passed.

Notes

1. This can be either handled on the R side (defer to the right React component depending on the prop passed), or JS side (a single component with a thin R wrapper).
2. We should take care to name the props properly, so it is clear to the user what they do.