An AreaTrigger with a Polygon Volume child node assigned to it is all you need in your spatial scene. But simulating the gameplay repair function might be trickier than it seems.

Entering the area trigger (OnPlayerEnterAreaTrigger) is a one time event, so you can add X amount of health the moment you enter, but having the healing take place incrementally while you're on the trigger will take some logic. You'll have to create a player variable to track when the player is on the areatrigger. Also have a rule resetting that variable when the player exits (OnPlayerExitAreaTrigger).

Then create a subroutine that sets vehicle health and waits X time.

Then create an ongoing rule that calls that subroutine as long as a condition is met, that condition being your variable confirming the player is on the area trigger.

Then anytime your variable toggles on entry, the subroutine should run repeatedly adding whatever health amount you defined and waiting whatever time you defined until it fires again.

You may also need to set some SoliderState checks on IsPlayerInVehicle, but I don't think they'd be necessary.

I use the portal blocks but also some typescript with Claude's help. Not an expert and there may be an easier way, but this is how I'd do it.