Bug: Plan approval in autopilot+fleet mode triggers execution with fleet dispatch ordering mismatch

## Description

When approving a plan in plan mode while using autopilot+fleet, the plan approval immediately triggers execution AND fleet agent dispatch simultaneously. The "Queued (1)" and "Fleet deployed" messages appear while the main agent is still "Analyzing bugs and planning fixes," suggesting a sequencing/ordering issue between the main agent's work and fleet dispatch.

## Steps to Reproduce

1. Enter plan mode and create a plan (e.g., with multiple bugs/features)
2. Switch to autopilot+fleet mode
3. Copilot recommends committing to the plan with autopilot+fleet
4. Approve/select that recommendation

## Expected Behavior

Plan approval should properly sequence execution — the main agent's analysis should be coordinated with fleet agent dispatch, not race against it.

## Actual Behavior

Fleet dispatch ("Queued (1)", "Fleet deployed") fires concurrently with the main agent beginning its "Analyzing bugs and planning fixes" phase. This ordering mismatch suggests the fleet agents are dispatched before the main agent has finished planning/coordinating the work.

## Screenshot

*(Screenshot shows: Plan approved -> "Analyzing bugs and planning fixes" starts -> "Queued (1)" / "Fleet deployed" messages appear simultaneously)*

## Environment

- OS: Windows
- Copilot CLI version: latest (as of April 2026)
- Mode: Autopilot + Fleet (experimental)

## Additional Context

Also submitted private feedback via the `/feedback` command for internal tracking.

Start by reproducing the plan approval flow in Windows autopilot+fleet mode and trace the transition from approval to the main agent's planning phase and fleet dispatch. Compare the ordering of those operations and identify where dispatch is triggered. Done means fleet deployment is coordinated with the main agent's planning rather than occurring concurrently, with the reported status messages appearing in the correct sequence.

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