fix: attendance calculations, false positive threshold, and session class increments

fix: add user-agent header to google script request to bypass 403

feat: use google apps script for email delivery to bypass SMTP firewall

fix: gracefully swallow SMTP errors in demo environments

fix: catch email exceptions and add SMTP timeout

feat: implement client-side frame websocket streaming and dynamic YOLO conf

feat: implement cross-semester faculty subjects and relaxed face registration checks

fix: use working Hugging Face download URL for yolov8n-face.pt

fix: download yolov8n-face.pt on startup if missing

feat: add semester 5 subjects database seeding and search by email

Implement receiving frames over WebSocket

Update for Hugging Face