Add world delta streaming and viewer smoothing

apps/backend/Contracts/WorldContracts.cs

@@ -3,6 +3,8 @@ namespace SpaceGame.Simulation.Api.Contracts;
 public sealed record WorldSnapshot(
   string Label,
   int Seed,
+  long Sequence,
+  int TickIntervalMs,
   DateTimeOffset GeneratedAtUtc,
   IReadOnlyList<SystemSnapshot> Systems,
   IReadOnlyList<ResourceNodeSnapshot> Nodes,
@@ -10,6 +12,24 @@ public sealed record WorldSnapshot(
   IReadOnlyList<ShipSnapshot> Ships,
   IReadOnlyList<FactionSnapshot> Factions);
 
+public sealed record WorldDelta(
+  long Sequence,
+  int TickIntervalMs,
+  DateTimeOffset GeneratedAtUtc,
+  bool RequiresSnapshotRefresh,
+  IReadOnlyList<SimulationEventRecord> Events,
+  IReadOnlyList<ResourceNodeDelta> Nodes,
+  IReadOnlyList<StationDelta> Stations,
+  IReadOnlyList<ShipDelta> Ships,
+  IReadOnlyList<FactionDelta> Factions);
+
+public sealed record SimulationEventRecord(
+  string EntityKind,
+  string EntityId,
+  string Kind,
+  string Message,
+  DateTimeOffset OccurredAtUtc);
+
 public sealed record SystemSnapshot(
   string Id,
   string Label,
@@ -33,6 +53,14 @@ public sealed record ResourceNodeSnapshot(
   float MaxOre,
   string ItemId);
 
+public sealed record ResourceNodeDelta(
+  string Id,
+  string SystemId,
+  Vector3Dto Position,
+  float OreRemaining,
+  float MaxOre,
+  string ItemId);
+
 public sealed record StationSnapshot(
   string Id,
   string Label,
@@ -45,6 +73,18 @@ public sealed record StationSnapshot(
   float RefinedStock,
   string FactionId);
 
+public sealed record StationDelta(
+  string Id,
+  string Label,
+  string Category,
+  string SystemId,
+  Vector3Dto Position,
+  string Color,
+  int DockedShips,
+  float OreStored,
+  float RefinedStock,
+  string FactionId);
+
 public sealed record ShipSnapshot(
   string Id,
   string Label,
@@ -52,6 +92,28 @@ public sealed record ShipSnapshot(
   string ShipClass,
   string SystemId,
   Vector3Dto Position,
+  Vector3Dto Velocity,
+  Vector3Dto TargetPosition,
+  string State,
+  string? OrderKind,
+  string DefaultBehaviorKind,
+  string ControllerTaskKind,
+  float Cargo,
+  float CargoCapacity,
+  string? CargoItemId,
+  string FactionId,
+  float Health,
+  IReadOnlyList<string> History);
+
+public sealed record ShipDelta(
+  string Id,
+  string Label,
+  string Role,
+  string ShipClass,
+  string SystemId,
+  Vector3Dto Position,
+  Vector3Dto Velocity,
+  Vector3Dto TargetPosition,
   string State,
   string? OrderKind,
   string DefaultBehaviorKind,
@@ -73,4 +135,14 @@ public sealed record FactionSnapshot(
   int ShipsBuilt,
   int ShipsLost);
 
+public sealed record FactionDelta(
+  string Id,
+  string Label,
+  string Color,
+  float Credits,
+  float OreMined,
+  float GoodsProduced,
+  int ShipsBuilt,
+  int ShipsLost);
+
 public sealed record Vector3Dto(float X, float Y, float Z);