update active vehicle id after insertion

TODO: find a more elegant way to do this, because it makes the Heuristic(s) responsible for updating a member of SAEVRoute
I could make it a member of BestInsertionHeuristic but then that means we have to instanciate an object to use the algorithms which seems inappropriate. Unless maybe if Heuristics classes ends up being delegate members of another class to allow heuristics/algorithms change via this delegate

src/algorithm/DARP/Heuristics/BestInsertionHeuristic.cpp

@@ -35,8 +35,16 @@ bool BestInsertionHeuristic::tryVehicleBestInsertion(size_t requestId, size_t ve
 size_t BestInsertionHeuristic::doBestRequestInsertionForRoute(size_t requestId, SAEVRoute route) {
     size_t vehicleId = 0;
     bool insertionSuccess{false};
+    //Iteratively try inserting in every active vehicle and the first inactive vehicle
     while(vehicleId <= route.getLastActiveVehicleId() + 1 && !insertionSuccess) {
         insertionSuccess = tryVehicleBestInsertion(requestId, vehicleId, route);
     }
+
+    //Update last active vehicle ID
+    if(vehicleId > route.getLastActiveVehicleId()) {
+        route.setLastActiveVehicleId(vehicleId);
+        DEBUG_MSG("NEW VEHICLE CREATED, ID :" + std::to_string(vehicleId));
+    }
+
     return vehicleId;
 }

src/routes/vehicle/SAEVRoute.h

@@ -18,6 +18,7 @@ private:
     size_t _nbRequest;
     const Graph* _graph;
     const std::vector<Request>* _requestList;
+    size_t _lastActiveVehicleId{0};
 public:
     SAEVRoute() = default;
     /**
@@ -123,6 +124,9 @@ public:
     [[nodiscard]] size_t getOriginDepotIdx(const size_t vehicleId) const { return _nbRequest*2 + vehicleId*2;}
     [[nodiscard]] size_t getDestinationDepotIdx(const size_t vehicleId) const { return _nbRequest*2 + vehicleId*2 + 1;}
 
+    [[nodiscard]] size_t getLastActiveVehicleId() const { return _lastActiveVehicleId; }
+    void setLastActiveVehicleId(size_t lastActiveVehicleId) { _lastActiveVehicleId = lastActiveVehicleId; }
+
     /**
      * Verifies that time windows have been properly propagated for a given vehicle's route
      * @param vehicleId