Report locked status to cthulhu. Should prevent some of the weirdness with the screen reader thinking it's in a different window.

i3lock.c

@@ -1335,7 +1335,9 @@ int main(int argc, char *argv[]) {
      * keyboard. */
     (void)load_keymap();
 
-    accessibility_feedback_start(xcb_get_file_descriptor(conn));
+    if (!accessibility_feedback_start(xcb_get_file_descriptor(conn))) {
+        errx(EXIT_FAILURE, "Could not initialize secure accessibility feedback");
+    }
     accessibility_feedback_notify(ACCESSIBILITY_SCREEN_LOCKED);
     update_modifier_feedback(true);