Implemented Role Based Access - STILL NEEDS fixing/testing

[angadk4]

Created a new system for RBAC. Essentially, individuals can now use a toggle at the top of the registration page to log in as either a teacher or student, which assigns the role of either "User" or "Teacher." Upon login, the system now uses an email query to verify whether the user is a teacher or student, and proceeds accordingly.

Changes Made:

• Added radio switch at the top of register.html page: can be on either the student or teacher position, but not both at once.
• Added relevant css styling for the role-switch in register.css.
• Updated relevant register.js code to add event listeners for the new role switch.
• Updated relevant register.js code to be able to retain position of switch upon failed attempt/redirect.
• Updated register.js code so that when in 'teacher' position, the grade field disappears and input for it is no longer needed for form submission.
• Updated register route in auth.py so the system now requests the role attribute, and based on "teacher" or "student" assigns a new User or Teacher model.
• Updated login route in auth.py so the system now uses the inputted email to determine whether the user is a teacher or student, and redirects accordingly.
• Added temporary teacher redirect page (we will decide what teachers should be able to do later).

Notes/Issues:

• IMPORTANT: Under models.py, the Teacher class had yrs_specialization set to Nullable=False. This was causing issues as the registration for teachers does not ask for this field, so it should be nullable in reality. I am not sure of how to migrate the database, so I would appreciate if someone could migrate the database with my new changes or show me how.
• IMPORTANT: For some reason, line 68 in auth.py (role = request.form.get("role")) is not functioning as intended. I am completely unsure why this issue exists, but it needs to be fixed for the RBAC system to work and be tested.