fix(plugins): trips.getById returns the actual trip row, not the access check

canAccessTrip only returns { id, user_id } (it's a membership check), but the
rpc-host's trips.getById returned it verbatim — so plugins saw a trip with no
title/start_date/etc. Fetch the real row after the access check. Also fix the
reference plugin to read t.title (the trips column is 'title', not 'name').

plugin-sdk/examples/trip-countdown/server/index.js

@@ -31,7 +31,7 @@ module.exports = definePlugin({
         return {
           status: 200,
           headers: json(),
-          body: JSON.stringify({ trip: t ? { name: t.name, days } : null }),
+          body: JSON.stringify({ trip: t ? { name: t.title, days } : null }),
         }
       },
     },