AnimatedModal: add disableBackdropClose prop (default false, no impact
on existing consumers). When true, overlay onClick is removed.
ProjectWizard: remove handleBackdropClick — backdrop click no longer
closes the wizard. Only the X button and Cancel close it.
EstimateWizard already had no backdrop-click handler; no change needed.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>