[FEATURE] Cowork scheduled tasks should be able to manage their own schedule or create bounded follow-ups

Problem

Cowork scheduled tasks appear to run in a restricted execution context that cannot manage scheduled tasks from inside the task itself.

That means a scheduled run cannot do common automation patterns such as:

• cancel or disable its own schedule once a stop condition is met
• adjust its next run based on what it just observed
• create a follow-up scheduled task as part of a multi-step workflow

This makes scheduled automations much less composable than normal Cowork runs.

Example use case

A periodic monitoring task runs every N minutes until it sees a success condition. Once that condition is detected, the natural next step is for the task to stop its own schedule (or replace itself with a lower-frequency follow-up task). Today that flow appears to be blocked by the scheduled-task restrictions.

Expected behavior

Scheduled Cowork runs should have a supported way to manage scheduling when acting on their own workflow, for example by allowing one or more of the following:

• self-cancel / self-disable
• self-update (change cadence)
• creation of a bounded follow-up scheduled task

If unrestricted nested scheduling is intentionally disallowed, a narrower policy would still help a lot:

• allow a scheduled task to modify or cancel only itself
• optionally allow creation of a single child/follow-up task with guardrails

Why this matters

Without this, many useful automations require a human to step back into the loop just to stop or re-shape a task that already has enough information to do the right thing.

The current behavior is understandable as a safety measure, but it feels stricter than necessary for self-management and simple handoff cases.

Suggested improvement

Either:

1. Support self-management for scheduled tasks directly, or
2. Document the restriction clearly and expose a safe alternative API/pattern for "stop when done" and "schedule follow-up" workflows.

Environment

• Cowork scheduled tasks
• Reproducible in the restricted scheduled-task execution context