Auto-offer /submit-for-review from /start after local test confirmation

[sebastientaggart]

Problem to Fix

When /start finishes writing code, the user tests locally and must then remember to type /submit-for-review. The handoff is mechanical but currently requires two distinct commands.

Why it Matters

Reducing a routine two-step into one prompt cuts friction without removing the human checkpoint (the local-test confirmation is still required).

General Approach

At the end of /start, instead of telling the user to run /submit-for-review, ask: "Tests passing — submit for review now? (yes / changes needed / scrap)". On yes, invoke the submit-for-review flow inline.

Complexity

Verification / QA effort: moderate
Touches two skills' interaction surface and the user's muscle memory; needs both happy path and "changes needed" path verified.

Acceptance Criteria

• /start's closing prompt offers inline submit instead of requiring a second command.
• "changes needed" returns to iteration without submitting.
• "scrap" still routes to make abandon.
• Typing /submit-for-review manually still works for users who prefer the explicit command.

Parent story

Part of #167.

[sebastientaggart]

Resolution

The closing prompt at the end of /start now invites you to reply yes to submit for review (or describe any changes) instead of asking you to remember and type a separate command. The same prompt is used whether you started fresh work or resumed an existing ticket.

See #173 for full technical details.