Inconsistent usage of terms "division" and "course level" (breaking change)

[matt-franklin225]

Expected Behavior

A previously mentioned in #190, the term "division" (which refers to undergraduate/postgraduate) is used in several places where the term "course level" (which refers to lower div/upper div/postgrad levels) should be used.

• On UCI's end, WebSoc refers to a class's course level (1-99, 100-199, 200+) with the term "division", so our scraper also has to use "division"
• Our endpoint for retrieving a class's course level also uses the term "division" instead of the more accurate "course level", so developers querying the API will have to use "division"
• Our codebase accurately uses the term "course level" to refer to this attribute except at the endpoint and in the scraper (such as in the names of functions and as enum variables)

Course level is the correct term to use here, division should only be used to refer to majors (e.g. a B.A. degree would be in the undergraduate division).

Possible Solution

The term "division" must be used in the scraper to retrieve the course level data, but the endpoint could be changed to use the term "course level", which would require a change to the schema for both grades.ts and websoc.ts. This would, however, be a breaking change as it would change the term that is used to query this information.

[laggycomputer]

This will also require breaking changes to libwebsoc-next.