fix: NPC_PutInVehicle not visually attaching NPC to boat seat

[Revelts]

Summary

Fixes #1225 — NPC_PutInVehicle updates logical state correctly (NPC_GetVehicle/NPC_GetVehicleSeat return expected values) but the NPC remains visually on foot for boats (tested with models 595 Launch, 446 Squalo).

Root cause

NPC::putInVehicle calls Vehicle::putPlayer, which sends the PutPlayerInVehicle RPC only to the entering player. For an NPC this is a no-op — it has no real client to receive the RPC. Other streamed-in clients receive no broadcast and must rely on the next periodic DriverSync to visually attach the NPC. While the SA-MP client auto-attaches a remote player to most vehicles from DriverSync alone, boats refuse to honour this when the local view still shows the player on foot, so the NPC stays visually on foot even though every server-side data structure agrees the NPC is the driver.

The natural goToVehicle flow does not have this problem because it emulates OnPlayerEnterVehicle first, whose handler broadcasts EnterVehicle to streamed players. That broadcast is the signal the SA-MP client needs to actually attach the NPC.

Fix

In Server/Components/NPCs/NPC/npc.cpp, inside NPC::putInVehicle, broadcast NetCode::RPC::EnterVehicle to streamed-in players immediately after Vehicle::putPlayer and the vehicle_ / vehicleSeat_ assignment. This mirrors the natural entry path without firing the OnPlayerEnterVehicle pawn callback.

NetCode::RPC::EnterVehicle enterVehicleRPC;
enterVehicleRPC.PlayerID = player_->getID();
enterVehicleRPC.VehicleID = vehicle.getID();
enterVehicleRPC.Passenger = (seat != 0) ? 1 : 0;
PacketHelper::broadcastToStreamed(enterVehicleRPC, *player_, true);

Test plan

• Spawn an NPC near a boat (model 595 Launch).
• Call NPC_PutInVehicle(npc, boatId, 0) from a command while a real player stands near the boat.
• Confirm the NPC visually attaches to the boat seat instead of staying on foot.
• Repeat for model 446 Squalo.
• Regression check: cars (any seated land vehicle) still work and the natural NPC_GoToVehicle flow is unaffected.
• Verify NPC_GetVehicle / NPC_GetVehicleSeat still return correct values.

Notes

• No SDK / ABI surface changes — fix is entirely inside the NPC component.
• PacketHelper and NetCode::RPC::EnterVehicle are already transitively included via netcode.hpp.
• Closes NPC_PutInVehicle does not visually attach NPC to boat seat #1225.