[Feature] Add KAIST verification endpoint

[injoonH]

Overview

Implement an option for users to verify if they belong to KAIST.
Create an auth_kaist table and establish a foreign key relationship with the auth_user table.

Describe the solution you'd like

Utilize the @kaistian/sso package to validate if a user belongs to KAIST.

Additional context

• Users can update their KAIST information by revalidating with their ID and password.
• One user can have multiple accounts, so the relationship between auth_user and auth_kaist is not one-to-one.