Add Stochastic flow matching for corrdiff

[daviddpruitt]

PhysicsNeMo Pull Request

Description

This change adds stochastic flowmatching to the existing CorrDiff implementation

Checklist

• [x] I am familiar with the Contributing Guidelines.
• [ ] New or existing tests cover these changes.
• [ ] The documentation is up to date with these changes.
• [ ] The CHANGELOG.md is up to date with these changes.
• [ ] An issue is linked to this pull request.

Dependencies

No additional dependencies required

[pzharrington]

I think all my main comments are in. Aside from minor things, I think the main thing to focus on is how much the additional SFM stuff can be absorbed into existing EDM functionality in PhysicsNemo. This will greatly help our efforts going forward in improving the usability/readability/extensibility of these modules.