The Core Workflow ran straight through and tended to fan out a whole set of screens unprompted. Reframe it as a design conversation: author one screen, show it, then STOP for explicit user approval before building the next (loop back to step 2 per screen). Multi-screen requests become a one-at-a-time queue. Closes T-307 (under UI epic T-276). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>