feat: auto create empty schedule when deleted all schedules (#552)

* feat: enhance schedule deletion to create a new schedule if none remain

* feat: set active index to new schedule if only one exists

* chore: run lint

* feat: enhance schedule deletion to create a new schedule if none remain

* feat: set active index to new schedule if only one exists

* chore: run lint

* feat: reset schedules on update, refactor invariant to within deleteSchedule

* chore: pnpm lint

---------

Co-authored-by: Samuel Gunter <29130894+Samathingamajig@users.noreply.github.com>
Co-authored-by: Samuel Gunter <sgunter@utexas.edu>

src/pages/background/lib/createSchedule.ts

@@ -36,5 +36,11 @@ export default async function createSchedule(scheduleName: string) {
     schedules.push(newSchedule);
 
     await UserScheduleStore.set('schedules', schedules);
+
+    // If there is only one schedule, set the active index to the new schedule
+    if (schedules.length <= 1) {
+        await UserScheduleStore.set('activeIndex', 0);
+    }
+
     return newSchedule.id;
 }