Refine ship orders and viewer controls

apps/backend/Ships/Api/ReorderShipOrderHandler.cs

@@ -0,0 +1,31 @@
+using FastEndpoints;
+
+namespace SpaceGame.Api.Ships.Api;
+
+public sealed class ReorderShipOrderHandler(WorldService worldService) : Endpoint<ShipOrderReorderRequest, ShipSnapshot>
+{
+    public override void Configure()
+    {
+        Put("/api/ships/{shipId}/orders/{orderId}/position");
+    }
+
+    public override async Task HandleAsync(ShipOrderReorderRequest request, CancellationToken cancellationToken)
+    {
+        var shipId = Route<string>("shipId");
+        var orderId = Route<string>("orderId");
+        if (string.IsNullOrWhiteSpace(shipId) || string.IsNullOrWhiteSpace(orderId))
+        {
+            await SendNotFoundAsync(cancellationToken);
+            return;
+        }
+
+        var snapshot = worldService.ReorderShipOrder(shipId, orderId, request);
+        if (snapshot is null)
+        {
+            await SendNotFoundAsync(cancellationToken);
+            return;
+        }
+
+        await SendOkAsync(snapshot, cancellationToken);
+    }
+}