Add public GeoJSON features API and load public 3D objects on maps.

Expose GET /v1/features/public (optional kind filter) and update Leaflet/MapLibre demos to render all public 3D assets globally, while still merging owner collections after login.

Made-with: Cursor

internal/store/postgres.go

@@ -260,6 +260,29 @@ func (s *PostgresStore) ListFeaturesByCollection(collectionID string) []Feature
 	return result
 }
 
+func (s *PostgresStore) ListFeaturesAll() []Feature {
+	rows, err := s.db.Query(
+		`SELECT id, collection_id, owner_key, type, geometry, properties, created_at, updated_at
+		 FROM features ORDER BY created_at`,
+	)
+	if err != nil {
+		return nil
+	}
+	defer rows.Close()
+	var result []Feature
+	for rows.Next() {
+		var f Feature
+		var geom, props []byte
+		if err := rows.Scan(&f.ID, &f.CollectionID, &f.OwnerKey, &f.Type, &geom, &props, &f.CreatedAt, &f.UpdatedAt); err != nil {
+			return result
+		}
+		_ = json.Unmarshal(geom, &f.Geometry)
+		_ = json.Unmarshal(props, &f.Properties)
+		result = append(result, f)
+	}
+	return result
+}
+
 func (s *PostgresStore) GetFeature(featureID string) (Feature, error) {
 	var f Feature
 	var geom, props []byte