fix: use spot.latitude/longitude for feedback (geometry no longer serialized)

frontend/src/components/SpotPanel/SpotPanel.jsx

@@ -102,10 +102,9 @@ function FeedbackButton({ spot }) {
   const submit = async (hasSeaweed) => {
     if (loading || sent) return;
     setLoading(true);
-    const coords = spot.geometry?.coordinates;
-    if (coords) {
+    if (spot.latitude != null && spot.longitude != null) {
       await api.feedback.create({
-        lat: coords[1], lng: coords[0],
+        lat: spot.latitude, lng: spot.longitude,
         hasSeaweed, coastalPointId: spot.id,
       }).catch(console.error);
     }