List students and guardians for a Google Classroom course using the Classroom roster and guardian APIs

Steps

1. Authenticate with OAuth 2.0 scopes for https://www.googleapis.com/auth/classroom.rosters.readonly and https://www.googleapis.com/auth/classroom.guardianlinks.students.readonly
2. GET /v1/courses/:courseId/students to retrieve the StudentSubmission list; paginate using nextPageToken until exhausted
3. For each student, extract the userId to use as the studentId in subsequent guardian lookups
4. GET /v1/userProfiles/:studentId/guardians to retrieve guardian invitation and acceptance records for each student
5. Filter guardians by invitedEmailAddress and the state field (COMPLETE for accepted, PENDING for invited but not yet accepted)
6. Aggregate the student-to-guardian mapping and store it for notification or reporting workflows