Add Applicant Log In QR Code for In-Persion Sessions

In the applicant Pin Popup menu, add an option to "Show QR code for Applicant Login Link" with the log in URL: https://exam.tools/portal/applicant/<team identifier>/<pin>

For in-person sessions, this would be a huge time saver during the login progress both for Tablet, BYOD, and paper/GradeCam exam formats.

Current state: applicants need to figure out how to get to exam.tools (is that even a website?!), look at the signs for the team identifier (or as a VE), look up their pin, and enter all that info to their personal device to trigger the login request for the VEs.

Desired state: VE pulls up the login QR code on their device, applicant scans it with their camera, and the VE can immediately authorize them to enter.