Use gh-aw temporary IDs for plan activation label targeting #1962

Parent: #1957

Problem

The plan activate workflow assumes create_issue returns a real GitHub issue number during the agent run. gh-aw defers issue creation to safe-output processing, so subsequent add_labels operations cannot safely target that number.

Scope

Correct the full /squad plan activate path to link create_issue and add_labels using explicit gh-aw temporary IDs. Do not change the /squad activate fast path in this issue.

Success criteria

• Every newly requested epic and task has a unique, valid gh-aw temporary_id.
• create-issue is configured to require temporary IDs if supported by the pinned gh-aw version.
• Each corresponding add_labels operation explicitly targets that same temporary ID.
• No operation relies on a real issue number being returned synchronously, predicted, or inferred.
• The triggering intent issue cannot receive an activated item’s owner label through an implicit target.
• Existing/reused issues are targeted only by a verified real issue number.
• squad, roster-owner, @copilot, multi-owner, and non-roster behavior remains consistent with the accepted activation contract.
• Targeted contract tests and strict gh-aw compilation pass.

Out of scope

Fast-path activation, summary reporting, capacity policy, checker distribution, and E4 execution.