Fix Emoji picker focus (#7217)

* Only portal the emoji picker where needed

* Add optional portal prop to emoji picker

* Use FocusScope to our advantage

* Pare back, add guards, fix focus trap

* Don't return focus to emoji button

* Set DM input position on emoji insert

* Let the caller determine next focus node

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Co-authored-by: Dan Abramov <dan.abramov@gmail.com>

src/view/com/composer/Composer.tsx

@@ -530,7 +530,14 @@ export const ComposePost = ({
   }
 
   const onEmojiButtonPress = useCallback(() => {
-    openEmojiPicker?.(textInput.current?.getCursorPosition())
+    const rect = textInput.current?.getCursorPosition()
+    if (rect) {
+      openEmojiPicker?.({
+        ...rect,
+        nextFocusRef:
+          textInput as unknown as React.MutableRefObject<HTMLElement>,
+      })
+    }
   }, [openEmojiPicker])
 
   const scrollViewRef = useAnimatedRef<Animated.ScrollView>()