FCNPCs can't drive trailers

[Naseband]

The plugin will refuse to seat NPCs into trailers (seat 0), although they are drivable. For example Model 607 (the luggage trailer) works fine for players and default NPCs, but they are marked as undrivable in the array data for FCNPC (the correct amount of seats for all trailers would be 1).

Instead, the plugin should check in FCNPC_ExitVehicle whether the NPC's current vehicle is a trailer and prevent the exit animations (use ClearAnimations to exit them).