Vouch Request: itsaryanchauhan - fix #3209 (imperative schedules invisible when no deployment)

[itsaryanchauhan]

Why do you want to contribute?

I'd like to fix #3209: imperative schedules created via schedules.create() are invisible in the Schedules UI when there's no current successful deployment, even though they exist in the DB, fire runs, and count against the schedule limit.

Root cause: ScheduleListPresenter bails out early when findCurrentWorkerFromEnvironment returns null. This early return made sense when possibleTasks was built from backgroundWorkerTask.findMany({ workerId: latestWorker.id }), but PR #3368 changed that query to getTaskIdentifiers(environmentId) which doesn't need a worker at all. The early return was never removed.

Fix is two files:

1. Remove the early return in ScheduleListPresenter.server.ts
2. Fix the blank-state condition in the schedules route so possibleTasks.length === 0 alone doesn't trigger "Create your first scheduled task" when imperative schedules exist

Prior contributions or relevant experience

I'm a CS student (graduating 2027) with hands-on TypeScript and React experience. I currently don't have merged OSS contributions to showcase. I've read the contributing guidelines, traced the bug to its root cause (the early return in ScheduleListPresenter that became stale after PR #3368 changed the possibleTasks query), and have the fix ready.

Portfolio: https://itsaryan.tech
GitHub: https://github.com/itsaryanchauhan

[itsaryanchauhan]

I've traced the root cause to the early return in ScheduleListPresenter.server.ts introduced in #1992 as a crash guard when possibleTasks depended on latestWorker.id. PR #3368 later changed that query to getTaskIdentifiers(environmentId) which doesn't need a worker at all, but the guard was never removed.

Fix involves two files - removing the early return in the presenter and fixing the blank-state condition in the route so imperative schedules are shown even when possibleTasks is empty. Fix is ready on my fork to be reviewed.