feat: add preloadItemCount for List, incase we need preload more items before scroll to end

doric-js/src/widget/list.ts

@@ -88,8 +88,8 @@ export class List extends Superview {
      * @param from 
      * @returns Returns the item of index which can dragged or not.
      */
-     @Property
-     itemCanDrag?: (from: number) => boolean
+    @Property
+    itemCanDrag?: (from: number) => boolean
 
     /**
      * @param from 
@@ -104,6 +104,9 @@ export class List extends Superview {
     @Property
     onDragged?: (from: number, to: number) => void
 
+    @Property
+    preloadItemCount?: number
+
     scrollToItem(context: BridgeContext, index: number, config?: { animated?: boolean, }) {
         const animated = config?.animated
         return this.nativeChannel(context, 'scrollToItem')({ index, animated, }) as Promise<any>