Fixes#812
When creating a "Monthly on weekday" recurring task, the selector would
jump back to Monday when trying to select Sunday. This was caused by using
the logical OR operator (||) instead of the nullish coalescing operator (??)
when handling the recurrence_weekday value.
Since Sunday is represented as 0, the || operator treated it as falsy and
defaulted to null/undefined, which then defaulted to 1 (Monday).
Changes:
- Replace || with ?? for recurrence_weekday in TaskRecurrenceCard.tsx
- Replace || with ?? for recurrence_weekday in TaskDetails.tsx
- Also fix recurrence_week_of_month and recurrence_month_day for consistency