Introducing @storyblok/richtext v5

Storyblok released v5 of its richtext package with a complete redesign of the rendering architecture focused on smaller bundles, better framework integration, and a simplified rendering system. The core package now ships at approximately 3.9 kB minified and gzipped, replacing the previous Tiptap-driven runtime with lightweight, framework-specific implementations, and introduces breaking changes requiring migration from v4.