Implement UI for agent scheduler

[linear]

The API is available under /graphs/schedules route.

This can be as simple as an input box on the monitor page for now.

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CRUD backend API:

/api/graphs/{graph_id}/schedules

In short:

If in scope, develop a feature on the Agent Runner page for scheduling agents. This includes selecting times and conditions under which agents should run. It needs to include updates to other ui elements to inform the users this agent instance is scheduled

[Torantulino]

@Abhi1992002 this would be a great ticket for you if you're interested!