[API-2] Update artifactual beats after editing beats in the beat editor

[ynwtnb]

Summary

The beat editor does not update detected artifactual beats as users make edits. However, MindWare interactively updates artifactual beats, helping users make corrections and confirm that their corrections are valid. Incorporating this functionality into PhysioView can improve usability and facilitate the transition from MindWare.

We can achieve it by developing a backend API that tracks edits and updates estimation (Related issue: #42 )

Acceptance criteria

• Set up a backend API that receives and updates edits made, and returns updated artifactual beat locations
• Connect the beat editor with the API so whenever users make edits, it posts the edit to the backend API and updates estimated artifacts

Reviewers

@nmy2103 , @ynwtnb , @tchen94