LocationHelper: Move clamp from zoomToFit to QML

The OSM plugin has a different zoom tolerance than what we're hardcoding
here. This fixes the map looking funky from being too zoomed while
trying to fit multiple location points at once.

(cherry picked from commit 15d6287995)

src/locationhelper.cpp

@@ -40,7 +40,7 @@ float LocationHelper::zoomToFit(const QRectF &r, float mapWidth, float mapHeight
     const auto zy = std::log2((mapHeight / (p2.y() - p1.y())));
     const auto z = std::min(zx, zy);
 
-    return std::clamp(z, 5.0, 18.0);
+    return z;
 }
 
 #include "moc_locationhelper.cpp"

src/qml/LocationsPage.qml

@@ -27,7 +27,10 @@ Kirigami.Page {
             let c = LocationHelper.center(LocationHelper.unite(locationsModel.boundingBox, liveLocationsModel.boundingBox));
             return QtPositioning.coordinate(c.y, c.x);
         }
-        map.zoomLevel: LocationHelper.zoomToFit(LocationHelper.unite(locationsModel.boundingBox, liveLocationsModel.boundingBox), mapView.width, mapView.height)
+        map.zoomLevel: {
+            const zoom = LocationHelper.zoomToFit(LocationHelper.unite(locationsModel.boundingBox, liveLocationsModel.boundingBox), mapView.width, mapView.height)
+            return Math.min(Math.max(zoom, map.minimumZoomLevel), map.maximumZoomLevel);
+        }
 
         MapItemView {
             Component.onCompleted: mapView.map.addMapItemView(this)