feat: Implement doctor availability and appointment limits

seed: comprehensive hospital simulation data — 15 patients, 30 appointments, medical records

feat: live queue sync — start/end/extend appointments, real-time patient notifications

feat: medical records system — patient health profile, medications, doctor entries, lab results, follow-ups

feat: patient reschedule request with doctor approve/reject flow

Merge branch 'main' into HF

fix: bundle doctors.json inside backend for HF deployment

feat(backend): add firebase push notification delivery

feat: add reminders service for managing medication reminders and occurrences

feat: Add Administrator Dashboard and Login Page

all files added