Big batch of UI updates (#276)

* Replace react-native-root-toast with a custom toast that fits the visual style

* Tune dark mode colors

* Tune colors a bit more

* Move the reply prompt to a fixed position in the footer

* Fully hide muted posts but give a control to show anyway (close #270)

* Improve thread rendering (better clarity on reply lines)

* Add follower/following counts to side menu

* Fix issues with display name overflows

src/view/com/post-thread/PostThread.tsx

@@ -96,7 +96,7 @@ export const PostThread = observer(function PostThread({
       onLayout={onLayout}
       onScrollToIndexFailed={onScrollToIndexFailed}
       style={s.hContentRegion}
-      contentContainerStyle={s.contentContainer}
+      contentContainerStyle={s.contentContainerExtra}
     />
   )
 })