Bring minimal `stalign` function

Description of feature

Ok here is the plan I have for this.

• We will only support point cloud case for now, later we can make additions.
• Will call it stalign and won't expose it as if it's a function that aligns everything. So that we can add other methods and have our monolith align function later as this goes
• If there is serious preprocessing needs to be done on point clouds it should be a different function called stalign_preprocess. If that is the case then there might be more optimal ways to handle this but let's just go with something we can ship as is.
• We shouldn't make guarantees on the stability of these unexposed API's
• plotting/scoring will be a separate issue
• I will do it in jax as it's better than torch and stalign doesn't rely on it so heavily