Simulates realistic "full screen design" orchestrator turns where
one dispatchElementToolCalls call handles 40-60 tools at once.
Coverage:
- 40-tool batch: <500ms end-to-end, 1 undo entry, 40 children, all
ids unique.
- 60-tool batch (upper bound): <800ms, all land, no id collisions.
- 3 × 20 consecutive batches: 60 total children, 3 undo entries,
global id uniqueness preserved across rounds.
- Promise.all of 3 parallel dispatches into 3 distinct roots: each
completes independently, full document id set remains unique.
The mixed pattern (heading + body + list-row + divider + stat-grid)
exercises multi-level tree inserts, not just flat heading stacks —
which is closer to what real AI orchestration emits.
Why the latency budget: AI thinking dominates generation time
(5-30s typical). The dispatch pipeline shouldn't be the bottleneck;
500ms for 40 tools = ~12ms per tool including store round-trip,
which is reasonable. A regression past this threshold signals
quadratic behavior somewhere in the pipeline.