Sasview database

[summerhenson]

Database backend in progress.

[krzywon]

In addition to my inline comments, a few general notes:

• I said this in the meeting, but wanted to reiterate it - good use of atomic commits with specific commit messages
• Some python formatting would be useful. Running everything through ruff could be worthwhile.
• Relative imports can be fragile, but mostly when trying to run a python file directly. That isn't easy with Django, so it's not that huge an issue, but wanted to mention it.
• Another thing we discussed at today's meeting, but wanted to mention again, is user auth and request.user clashes. Many of the checks don't ensure the authenticated user is the data owner.

Overall, a good start to the project. I'll try to make comments every week, or as updates are made.