Fix scheduler task detail modal close flow

[ruizanthony]

Summary

• track when the scheduler task detail modal was opened from the Tasks modal
• close the parent Tasks modal when dismissing the task detail view
• keep the edit flow working by focusing/reopening the Tasks modal before showing the editor

Testing

• node --check webui/components/modals/scheduler/scheduler-store.js
• git diff --check -- webui/components/modals/scheduler/scheduler-store.js
• Manually verified in the UI that closing task detail no longer leaves the Tasks popup stuck open