Gateway: APNs topic is the watch app's bundle ID

docs/plan.md

@@ -200,4 +200,6 @@ they push to `docs/`.
   hosts).
 - CI deploys right away through a `wristcode` entry in `~/Server/ci-deploy.sh`, with Watchtower's
   nightly pull as the fallback.
-- The bundle ID is `org.gbrown.wristcode`.
+- The App Store record uses `org.gbrown.wristcode`, an empty iOS wrapper the App Store requires
+  around a watch-only app. The watch app itself is `org.gbrown.wristcode.watchkitapp`, which is also
+  its APNs topic.