Add Craft.js site builder (v2) - complete rebuild from GrapesJS

Rebuilt the visual site builder from scratch using Craft.js, React 18,
and TypeScript. The new editor renders directly in the DOM (no iframe),
supports 40+ components, multi-page with shared header/footer, 16
templates, full-spectrum color/gradient controls, custom head code
injection, save/publish workflow, and auto-save.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

craft/src/panels/right/styles/index.ts

@@ -0,0 +1,13 @@
+export { TextStylePanel } from './TextStylePanel';
+export { ButtonStylePanel } from './ButtonStylePanel';
+export { ImageStylePanel } from './ImageStylePanel';
+export { ContainerStylePanel } from './ContainerStylePanel';
+export { HeroStylePanel } from './HeroStylePanel';
+export { NavStylePanel } from './NavStylePanel';
+export { MediaStylePanel } from './MediaStylePanel';
+export { FormStylePanel } from './FormStylePanel';
+export { SocialStylePanel } from './SocialStylePanel';
+export { SectionTypePanel } from './SectionTypePanel';
+export { PricingStylePanel } from './PricingStylePanel';
+export { BackgroundSectionStylePanel } from './BackgroundSectionStylePanel';
+export { GenericPropsEditor } from './GenericPropsEditor';