Separate views per day when creating weekly schedules

[chrisbenincasa]

In the time slot editor page, when creating a weekly schedule, we should not present all time slots in a flattened list. Instead, we should have some sort of secondary navigation across days.

In addition, there might be better ways to present what the current schedule looks like overall. I think this will also help performance since there seems to be a bottleneck in rendering many (>10) TimePickers from MUI-X at once.