Function withInsertedWaypoint

withInsertedWaypoint(
    route: Route,
    existingWaypoints: WaypointLike[],
    newWaypoint: WaypointLike,
): WaypointLike[]
Returns a new array of waypoints with the new waypoint inserted at the optimal position.

It finds the best insertion index and inserts the waypoint in one step, using findBestWaypointInsertionIndex to find where the waypoint fits most naturally along the route.
Parameters
- route: Route
  The existing calculated route, a Feature with LineString geometry.
- existingWaypoints: WaypointLike[]
  The existing waypoints in order, from origin through intermediate waypoints to destination.
- newWaypoint: WaypointLike
Returns WaypointLike[]
A new array with the waypoint inserted at the optimal position.
Remarks
- It returns a new array and leaves the original waypoints array unmodified.
- It places the waypoint with the same logic as findBestWaypointInsertionIndex, which says what it does with a route of fewer than 2 coordinates or fewer than 2 waypoints.
Example
```
// A route from [4.9, 52.3] to [5.0, 52.4], through [4.95, 52.35]
const updatedWaypoints = withInsertedWaypoint(route, [[4.9, 52.3], [5.0, 52.4]], [4.95, 52.35]);
// Returns: [[4.9, 52.3], [4.95, 52.35], [5.0, 52.4]]
```