Child Slots, Supabase, Shaders & New Aspect Ratio Widget

This release introduces Supabase OAuth integration for streamlined setup, custom shader uploads for ShaderFill and ShadeWrapper widgets, and a new AspectRatio widget with preset and custom ratio support. Improvements include radial gradient and chart conversion from Designer, higher-quality PDF previews, dynamic-height radio buttons, and offline Local Run support. Plus 31 bug fixes addressing build failures, crashes, code export issues, and more.