Use contentInset for Dynamic ScrollView Spacing

When adding space to the top or bottom of a ScrollView that may change (keyboard, toolbars, dynamic content), use contentInset instead of padding. Changing contentInset doesn't trigger layout recalculation—it adjusts the scroll area without re-rendering content.

Incorrect (padding causes layout recalculation):

function Feed({ bottomOffset }: { bottomOffset: number }) {
  return (
    <ScrollView contentContainerStyle={{ paddingBottom: bottomOffset }}>
      {children}
    </ScrollView>
  )
}
// Changing bottomOffset triggers full layout recalculation

Correct (contentInset for dynamic spacing):

function Feed({ bottomOffset }: { bottomOffset: number }) {
  return (
    <ScrollView
      contentInset={{ bottom: bottomOffset }}
      scrollIndicatorInsets={{ bottom: bottomOffset }}
    >
      {children}
    </ScrollView>
  )
}
// Changing bottomOffset only adjusts scroll bounds

Use scrollIndicatorInsets alongside contentInset to keep the scroll indicator aligned. For static spacing that never changes, padding is fine.