Refresh planner queue after x402 guardrail

[asim]

Summary:

• Drop the closed x402 spend-budget guardrail item from the planner queue.
• Add Propagate agent run cancellation and deadlines through model and tool calls #4750 as the next top priority for cancellation/deadline propagation across agent runs.

Testing:

• git diff --check

Closes #4749

[Copilot]

Pull request overview

Updates the autonomous planner’s ranked work queue to reflect the latest closed guardrail work and to prioritize the next agent-harness gap (cancellation/deadline propagation), aligning the loop queue with the current roadmap and open issues.

Changes:

• Replaces the now-closed x402 spend-budget guardrail queue item with the cancellation/deadline propagation item (#4750).
• Updates the queue rationale to reference the closing PR for the x402 guardrail work (#4748).

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