Architect run dispatches its plan as a Spec run or a Run #232

Parent

#27

What to build

Without --plan-only, once the plan is marked ready-for-agent, the Architect run dispatches it as thirdshift <plan URL> would: a Spec run when the plan has sub-issues, a Run otherwise. merge/no-merge, the User config's merge default and parallel <n> apply to it as if they had been given to that command. The dispatched run's outcome, exit status and printed PR URL become the Architect run's.

Acceptance criteria

• A plan with Tickets starts a Spec run on it, end to end with the fake claude and gh.
• A single-Ticket plan starts a Run on it.
• merge, no-merge and the User config's merge default apply to the Spec PR or the Run's pull request; contradictory flags are rejected.
• parallel <n> passes through to a Spec run, and is rejected or reported as for thirdshift <Issue URL> when the plan isn't a Spec.
• merge, no-merge or parallel with --plan-only is rejected, since nothing is dispatched for them to apply to.
• The Architect run exits with the dispatched run's status and prints its PR URL.
• Progress lines show the dispatch; the README describes it.

Blocked by

• thirdshift architect --plan-only: the Architecture review publishes a plan and thirdshift marks it ready #230