
Using a starting time other than 0:00 will prevent events before the chosen starting time from showing up for that range. This was causing events before 12:00 to be missing in the shell calendar on the first day of a range. Fix this by always starting at 0:00 and then incrementing by days rather than a time value that depending on DST or leap seconds may or may not correspond to a day. Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2023>