Feature: "Dormant" / "Scheduled" session state in agents view for background monitors using ScheduleWakeup

Summary

When a background monitor calls ScheduleWakeup and ends its turn, agents view has no way to express that the session is intentionally sleeping until the next scheduled fire. It shows as either Working (if a cron was holding the session open — old pattern) or disappears from view entirely. Neither is correct.

Desired behavior

After a session calls ScheduleWakeup and completes its turn, agents view should show it as Scheduled (or Dormant), ideally with the next fire time visible — e.g.:

tickler   Scheduled · next check 8:03 AM

This makes it immediately clear to the user that:

• The session is alive and intentionally idle (not crashed, not done)
• When it will run next
• It is not consuming resources between cycles

Current behavior

• With CronCreate (old pattern): session stays open as Working indefinitely — misleading, prevents the session from looking idle
• With ScheduleWakeup (correct pattern): session disappears or shows as Done — user has no visibility into when it will fire next

Context

This came up building a PR/issue watcher (tickler) plugin. Switched from CronCreate to ScheduleWakeup specifically to fix the perpetual \"Working\" state. But now the session simply vanishes between cycles, which is better but still not ideal — the user doesn't know the monitor is still active.

A lightweight Scheduled state shown in agents view between ScheduleWakeup fires would complete the model.

Related

• #47518 — visibility into scheduled wakeups / background monitoring
• #55981 — async/event-driven communication for agents
• #48965 — multi-session coordination primitives