feat: add course type field to advanced settings and course info index

[andrey-canon]

Description

Introduces a new Course Type advanced setting, allowing students to filter courses by topic or interest.

How to test

1. Go to the advanced setting section and check course Type option. (course authoring)
   Fill it and save

Screencast.from.29-09-25.15.55.33.webm

2. Check in mongo the data was saved (Optional)

docker exec -it tutor_main_dev-mongodb-1 bash
mongosh openedx
db.modulestore.structures.find().sort({ edited_on: -1 }).limit(3)

Issue #1484
Migration pr of #62

[johanseto]

Working in my local env.

As an improvement could the cherry-pick commit info include its parent in the commit body