chore: add ref design assets and docs

ref/CSP-Minecraft-UI-Kit/README.md

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+# CSP Learning Platform - Minecraft Style UI Kit
+
+This package contains all downloadable UI kit resources for the CSP learning platform.
+
+## Folder layout
+
+- ui-kit: core UI kit images
+- pages: full page designs
+- responsive: responsive showcase
+- dev-guide: CSS naming and implementation guide
+- docs: delivery document and preview image
+- images: icons, textures, badges, and UI decorative assets
+
+## Source link
+
+- HTML doc: https://assets-persist.lovart.ai/agent_images/000728ad-aef9-4cc9-80b4-a333b1a29d44.html