As an admin, I want to have an overview of all appointments with specific PICs so that I know which appointment is handled by which employee

[hongtuyet91]

A/C:

• Display all appointment requests submitted by residents in a table. Users are able to filter by columns as they want
• For every appointment, employee can see if that appointment is already taken by a PIC or not (show the name of PIC or button "Accept" is still available)