Book several seats at once on group pages

When one person signs up a whole team for your session, they shouldn't have to book it five times. Group booking pages now ask how many people are coming at the moment it matters.

What's new:

• How many people, right after the time – After choosing a time, invitees see a card asking how many people are coming, with a −/+ stepper and a Continue button.

• Never more than what's free – The stepper stops at the number of seats still open for that slot.

• Show seats left – A new event type setting shows the free seats next to every time, for example "15:00 · 7 seats left". It's off by default.

• Group and round robin – The setting appears on group event types, and on round robin event types once "Allow multiple invitees" is on.

Why this matters: Picture a training provider or a fitness studio running group sessions. When the seat field was easy to miss, invitees booked each person separately, and the attendee list filled up with duplicate bookings under the same email. Now one booking covers the whole group, and seeing that only a few seats are left gives people a reason to book before the session fills up.