Draft: Button to redirect a request to head TA/lecturer

What does this mr do?

Closes #628

This MR adds the option for TAs to forward requests to all staff (head TAs and lecturers, but not simple TAs), without choosing the specific staff person. Then the forwarded request is visible only to staff and can only be picked up by staff.

Screenshots

before

after

Somebody forwards the request to staff: Simple TA cannot see the request or pick it up: A head TA can see and pick up the request:

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made.
• Tests were created to test the feature.
• I have updated the documentation accordingly.
• I adhere to the style guide.