Fix ObjectBox connections DB to properly handle adds which shouldn't replace

lib/data/objectbox/objectbox_connections_repo.dart

@@ -24,15 +24,18 @@ class ObjectBoxConnectionsRepo implements IConnectionsRepo {
 
   @override
   bool addAllConnections(Iterable<Connection> newConnections) {
-    memCache.addAllConnections(newConnections);
-    final result = box.putMany(newConnections.toList());
-    return result.length == newConnections.length;
+    var allNew = true;
+    for (final c in newConnections) {
+      allNew &= addConnection(c);
+    }
+    return allNew;
   }
 
   @override
   bool addConnection(Connection connection) {
-    memCache.addConnection(connection);
-    box.putAsync(connection);
+    if (memCache.addConnection(connection)) {
+      box.putAsync(connection);
+    }
     return true;
   }