Summary
- Add nullable projectId field to TaskScheduleInstance.
- Create an index for TaskScheduleInstance.environmentId (added only if
it doesn’t exist, handled concurrently).
- Ensure TaskScheduleInstance.projectId is set everywhere in the
codebase.
Backfilling projectIds, once this is live
```sql
UPDATE "TaskScheduleInstance" tsi
SET "projectId" = ts."projectId"
FROM "TaskSchedule" ts
WHERE tsi."taskScheduleId" = ts."id";
```
Matt Aitken
b696bbb1df