Add migrations to version control

[wkyoshida]

Terms

• I have searched open and closed issues
• I agree to follow activist's Code of Conduct

Issue

This issue is to start saving the needed migrations to the database in version control.

We can use the issue to discuss:

• When to actually start
  • Likely once we deem the backend to be in a "ready-enough" state
• When and how to generate future migration files based on new changes to the backend
  • Included in PRs? After a PR is merged?

cc: @andrewtavis, @to-sta

[Mitadru17]

sir I would like to work on this issue. Please assign me this issue.