MainScreenComponent class

Adaptive layout widget powering MediaSFU's spotlight/gallery split.

• Computes child dimensions responsively based on mainSize, doStack, and screen orientation. Wide screens (aspect ratio ≥ 1) apply fractional sizing; narrow screens stack children vertically.
• Invokes updateComponentSizes whenever layout metrics change, delivering ComponentSizes so external controllers can adjust pagination, overlays, or helper positioning.
• Provides three builder hooks: containerBuilder (wrap the entire component), childrenBuilder (wrap the row/column that holds children), and childBuilder (wrap each individual child).
• Respects showControls by reserving (1 - defaultFraction) of the height for an action bar.

Use this widget in MediasfuUICustomOverrides.mainScreen to deliver custom spotlight arrangements, branded theming, or alternative child layouts.

Example:

MainScreenComponent(
  options: MainScreenComponentOptions(
    mainSize: 70,
    doStack: true,
    containerWidthFraction: 0.5,
    containerHeightFraction: 0.5,
    updateComponentSizes: (sizes) => print('Updated sizes: $sizes'),
    defaultFraction: 0.9,
    showControls: true,
    children: [
    ChildComponent1(),
    ChildComponent2(),
   ],
  ),
);

Notes:

• The component adjusts layout direction (horizontal or vertical) based on screen width.
• The updateComponentSizes callback provides updated component dimensions for responsive adjustments.