ResizeDetector

Primitive #53

🔍 Problem it solves

Components need to react when their container size changes (e.g., responsive charts, adaptive layouts). The `window.resize` event doesn't detect size changes of individual elements.

✅ Solution

ResizeDetector uses `ResizeObserver` to detect size changes of a specific element. It provides new width, height, and content box dimensions. Subscribers are notified on each resize.

🧩 Used by components

ResponsiveChart, AdaptiveComponent, DashboardWidget, TextareaAutosize, SplitPane

🎮 Interactive demo