Move email column from personal_info to user table [BE]

[ssihala]

To support password reset functionality, we will require users to provide an email when making an account. This needs to be stored in the user table (it is currently a column in the personal_info table)

Tasks:

• Change the DB scheme as mentioned above
• Adjust auth.ts: the signup and login routes need to be adjusted to account for the new email. The user will now pass username, password, and email when signing up.
• If needed, coordinate with frontend to figure out what formData is being passed to the backend.

TEST THIS BEFORE PUSHING, DON'T BREAK ANYTHING