Before mounting any legacy build tool, ToolManager checks whether the
active tool's kind has a registered NodeDefinition with a tool
contribution. If yes, the registry tool wins; the legacy tool map and
special-cased spawn/column/elevator branches are skipped for that kind.
Lazy-loaded via React.lazy (cached by loader) and wrapped in Suspense.
Today the registry is empty, so useRegistryTool is always false and
every code path renders unchanged. The moment a kind registers (Phase
2+), its registry tool takes over without further edits here.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
