Add Background Check Status Tab to Annual Report

Issue Description

Add a new Background Check Status tab to the Download Annual Report spreadsheet.

This tab should include students whose background check status is currently Not Submitted or Submitted. The report should be limited to students who are relevant to CELTS volunteer and program participation, including:

Interested volunteers/students
Students who have volunteered
CELTS Student Staff
Operations Team members
Bonner Scholars

Students who are marked as graduated should not be included in this report.

The purpose of this tab is to give CELTS staff a clear list of students whose background checks are still incomplete or awaiting processing.

No files or tests are named. Start by locating the Download Annual Report implementation and reviewing how its existing spreadsheet tabs select students; add the Background Check Status tab with the stated status and participation filters, excluding graduated students, and verify that the resulting list matches those rules.

Written by the indexing model from the issue text.