Remove TS annotation from define:vars script (caused parse error)

site/src/layouts/Base.astro

@@ -822,7 +822,7 @@ try {
           stravaStatus.textContent = 'Waiting for Strava authorisation…';
 
           // postMessage listener — works cross-origin (callback may be on a different subdomain)
-          function onStravaMsg(e: MessageEvent) {
+          function onStravaMsg(e) {
             if (!e.data || e.data.stravaAuth === undefined) return;
             window.removeEventListener('message', onStravaMsg);
             clearInterval(closedPoll);