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/com/util/post-embeds/index.tsx

@@ -136,7 +136,10 @@ export function PostEmbeds({
                 <Pressable
                   onPress={() => {
                     onPressAltText(alt)
-                  }}>
+                  }}
+                  accessibilityRole="button"
+                  accessibilityLabel="View alt text"
+                  accessibilityHint="Opens modal with alt text">
                   <Text style={styles.alt}>ALT</Text>
                 </Pressable>
               )}