Booking timetable and staff scheduling are more reliable

Adding a new staff member and their working hours in the same save could fail with a confusing error, and the booking calendar's open-hours shading wasn't lining up with the actual time grid. Both are fixed. You can also now mark a single staff member as off on a specific date — a holiday or appointment — without closing the whole business, alongside your existing whole-business closures like bank holidays. The Bookings page has also been reorganised into clear tabs (Requests, Calendar, Services & hours, Staff) so everything is easier to find.