Infinite scroll

Add action when user go to the bottom of page like $load, $pull and etc....
for implementing the infinite scrolling.....

The issue names infinite scrolling and the `$load` and `$pull` actions, but it does not identify files, tests, or an entry point. First locate how actions and page-bottom events are handled, then clarify the expected trigger and completion behavior; done should include a working infinite-scroll flow with coverage for the new behavior.

Written by the indexing model from the issue text.