[APP-724] Collection of accessibility fixes (#949)

* Fix: include alt text on the web lightbox image

* a11y: Dont read the 'ALT' label

* a11y: remove a wrapper behavior from posts

This appears to have been introduced with the goal of creating meta
actions on posts, but the behavior seems counter-productive. The
accessibility inspector was unable to access individual items within
the post and therefore most content was simply skipped.

There may be a way to support the post actions without losing the
ability to access the inner elements but I couldnt find it. -prf

* a11y: apply alt tags to image wrappers so they get read

* a11y: set Link accessibilityLabel to the title if none set

* a11y: skip the SANDBOX watermark

* a11y: improve post meta to not read UI and give a useful date

* ally: improve post controls

* a11y: add labels to lightbox images on mobile

* fix types

src/view/com/util/post-ctrls/PostCtrls.tsx

@@ -19,6 +19,7 @@ import {Text} from '../text/Text'
 import {PostDropdownBtn} from '../forms/DropdownButton'
 import {HeartIcon, HeartIconSolid, CommentBottomArrow} from 'lib/icons'
 import {s, colors} from 'lib/styles'
+import {pluralize} from 'lib/strings/helpers'
 import {useTheme} from 'lib/ThemeContext'
 import {useStores} from 'state/index'
 import {RepostButton} from './RepostButton'
@@ -170,7 +171,9 @@ export function PostCtrls(opts: PostCtrlsOpts) {
         hitSlop={HITSLOP}
         onPress={opts.onPressReply}
         accessibilityRole="button"
-        accessibilityLabel="Reply"
+        accessibilityLabel={`Reply (${opts.replyCount} ${
+          opts.replyCount === 1 ? 'reply' : 'replies'
+        })`}
         accessibilityHint="reply composer">
         <CommentBottomArrow
           style={[defaultCtrlColor, opts.big ? s.mt2 : styles.mt1]}
@@ -190,7 +193,9 @@ export function PostCtrls(opts: PostCtrlsOpts) {
         hitSlop={HITSLOP}
         onPress={onPressToggleLikeWrapper}
         accessibilityRole="button"
-        accessibilityLabel={opts.isLiked ? 'Unlike' : 'Like'}
+        accessibilityLabel={`${opts.isLiked ? 'Unlike' : 'Like'} (${
+          opts.likeCount
+        } ${pluralize(opts.likeCount || 0, 'like')})`}
         accessibilityHint="">
         {opts.isLiked ? (
           <HeartIconSolid