Save the state of a degree plan

[joalen]

Currently, if you refresh the page, all of the terms added and the courses drag-and-dropped will be wiped.

The goal here is to be able to not just have functionality (in the form of a button) that allows a student to save their changes on a degree plan BUT have smart ways of saving it to local and to the cloud. A really good system we can do and maybe opens up doors to allow others to collaborate on degree plans is this...

1. Use a CRDT approach in which we maintain what was changed, rather than the entire context
2. If a user is offline + maybe some sort of offline time (we can keep some sort of session cookie that tracks usage of our planner), we can "upsert" those changes and have it be maintained while saving up on API usage (maybe we can have a CRUD operation for this like updatePlanner or smth like that)

[joalen]

Ok, ignore the whole CRDT approach I had; that's lowkey overkill but a good feature to have for when we introduce "collaborative degree planning" <-- might be sometime in the future, like 3.0 or 3.5 I guess (not yet for sure)

Just implement a save button maybe within the sidebar or on the actual degree planner interface that lets the student know to save their plan. We can also have it to where, if they try to close the tab without saving, we show that same warning box of unsaved changes you'd normally find in most pages that need to save.

Again, Oscar can help you plan a good JSON payload to create a "save state" or maybe add it to evaluation.json? Whatever the format is, it'll store into the students S3 folder and preferably, we should add some metadata indicating the last known update date.