don't bump timeline when adding notes

This is quite different than Damus iOS. The timeline will continually
add new items without bumping scroll position, thanks to
egui-virtual-list's `items_inserted_at_start` function.

Closes: https://github.com/damus-io/notedeck/issues/38
Fixes: https://github.com/damus-io/notedeck/issues/59
Signed-off-by: William Casarin <jb55@jb55.com>

src/timeline.rs

@@ -153,6 +153,7 @@ pub fn timeline_view(ui: &mut egui::Ui, app: &mut Damus, timeline: usize) {
     ui.add_space(3.0);
 
     egui::ScrollArea::vertical()
+        .animated(false)
         .scroll_bar_visibility(ScrollBarVisibility::AlwaysVisible)
         .show(ui, |ui| {
             let len = app.timelines[timeline].notes.len();