Fixes suggested by Jordan / Luke

[AaDalal]

• support for fulfilling with 3 digit codes
• make the general course search more clear on the UI
• make the root font-size smaller so the UI is less cramped
• make year a free input field
• make edit mode not turn off when you add or delete a semester
• course credits are sometimes wrong. Two potential root causes:
  • credits sql is wrong (e.g., MATH 1400 is not 2 credits)
  • course with no credits defaults to 1 CU on the frontend. Need to make sure we get the course of that code with credits from the backend.

For a later pr:

• add clear course dock button -> need to make sure this doesn't lead to some weird state with fulfillments (jordan in Add a dock clear button #648)
• fix issues with radix ui select menus being partially hidden

[JHawk0224]

❤️