Appointment booking for a solo pro

Build a Calendly-style booking page for a solo professional (coach, therapist, consultant).

Core features:
1. Public page with services, duration, price
2. Availability from Google Calendar (busy times block slots)
3. Booking flow with intake questions and Stripe payment (or deposit)
4. Confirmation + calendar invite + reminder emails
5. Reschedule/cancel links

Data: services, availability_rules, bookings, intake_answers.
Must-haves: timezone-safe, buffer times, no double booking.