React Native accessibility (#539)

* React Native accessibility

* First round of changes

* Latest update

* Checkpoint

* Wrap up

* Lint

* Remove unhelpful image hints

* Fix navigation

* Fix rebase and lint

* Mitigate an known issue with the password entry in login

* Fix composer dismiss

* Remove focus on input elements for web

* Remove i and npm

* pls work

* Remove stray declaration

* Regenerate yarn.lock

---------

Co-authored-by: Paul Frazee <pfrazee@gmail.com>

src/view/shell/Composer.web.tsx

@@ -31,7 +31,7 @@ export const Composer = observer(
     }
 
     return (
-      <View style={styles.mask}>
+      <View style={styles.mask} aria-modal accessibilityViewIsModal>
         <View style={[styles.container, pal.view, pal.border]}>
           <ComposePost
             replyTo={replyTo}