feat: Add metro transit, gadgets, shop, social apps, and traffic models checkpoint

Ananta.Server/Ananta.App/PrivateServerApplication.cs

@@ -7,6 +7,7 @@ using Ananta.Server.Handlers.LoginGate;
 using Ananta.Server.Protocol.Client4229938;
 using Ananta.Server.Gameplay.Traffic;
 using Ananta.Server.Gameplay.Crowd;
+using Ananta.Server.Gameplay.World;
 using Ananta.Server.Network;
 
 namespace Ananta.Server.App;
@@ -48,6 +49,14 @@ internal sealed class PrivateServerApplication(PrivateServerConfig config)
             TrafficAndCrowdDriver.Instance,
             () => gameSessions.Current is not null ? [gameSessions.Current] : Array.Empty<TcpSession>());
 
+        // Interactive gadget + scene-item grid streaming (vending machines, arcades, doors,
+        // lampposts, props from the client's baked cell data) — server-side equivalent of the
+        // AnantaGadgetLoader / AnantaWorldMod injects.
+        GadgetStreamingEngine.Instance.Initialize(
+            clientDataFolder,
+            TrafficAndCrowdDriver.Instance,
+            () => gameSessions.Current is not null ? [gameSessions.Current] : Array.Empty<TcpSession>());
+
         // Localhost debug API for debug-panel.py (optional, never blocks the game stack).
         using var debugApi = config.Debug.Enabled ? new DebugApiServer(config, gameSessions) : null;
         var webInfo = "web=off";