improved large album/playlist performance

switched to flatlist for all of those

app/components/ImageGradientFlatList.tsx

@@ -0,0 +1,13 @@
+import React from 'react'
+import BackgroundHeaderFlatList, { BackgroundHeaderFlatListPropsBase } from './BackgroundHeaderFlatList'
+import ImageGradientBackground, { ImageGradientBackgroundProps } from './ImageGradientBackground'
+
+export type ImageGradientFlatListProps<ItemT> = BackgroundHeaderFlatListPropsBase<ItemT> & {
+  backgroundProps?: ImageGradientBackgroundProps
+}
+
+function ImageGradientFlatList<ItemT>(props: ImageGradientFlatListProps<ItemT>) {
+  return <BackgroundHeaderFlatList BackgroundComponent={ImageGradientBackground} {...props} />
+}
+
+export default ImageGradientFlatList