fix(combat): track targets with retail camera

Port ClientCombatSystem's Keep in View consumer through CameraSet's pivot-to-target boom heading, including the transformed half-metre target offset and melee/missile validity gates. Preserve the existing stateful chase damping and collision architecture, with conformance coverage and named-retail pseudocode.

Co-Authored-By: Codex <codex@openai.com>

src/AcDream.App/Rendering/GameWindow.cs

@@ -8415,13 +8415,15 @@ public sealed class GameWindow : IDisposable
             // player visibly rises in frame without the camera
             // swinging vertically (was the symptom of using raw
             // velocity-vector heading).
+            System.Numerics.Vector3? trackedCombatTarget = GetCombatCameraTargetPoint();
             _retailChaseCamera!.Update(result.RenderPosition, _playerController.Yaw,
                 playerVelocity:     _playerController.BodyVelocity,
                 isOnGround:         result.IsOnGround,
                 contactPlaneNormal: _playerController.ContactPlane.Normal,
                 dt:                 (float)dt,
                 cellId:             _playerController.CellId,
-                selfEntityId:       _playerController.LocalEntityId);
+                selfEntityId:       _playerController.LocalEntityId,
+                trackedTargetPoint: trackedCombatTarget);
 
             // Send outbound movement messages to the live server.
             if (_liveSession is not null)
@@ -12021,6 +12023,26 @@ public sealed class GameWindow : IDisposable
         return SelectClosestCombatTarget(showToast: false);
     }
 
+    /// <summary>
+    /// Resolves retail's combat-camera target. ClientCombatSystem::
+    /// UpdateTargetTracking (0x0056A950) enables CameraSet::TrackTarget only
+    /// for melee/missile combat with the option enabled and a valid attack
+    /// target. TrackTarget applies target-local offset (0,0,0.5).
+    /// </summary>
+    private System.Numerics.Vector3? GetCombatCameraTargetPoint()
+    {
+        if (!_persistedGameplay.ViewCombatTarget
+            || !AcDream.Core.Combat.CombatInputPlanner.SupportsTargetedAttack(Combat.CurrentMode)
+            || _selection.SelectedObjectId is not uint selected
+            || !IsLiveCreatureTarget(selected)
+            || !_entitiesByServerGuid.TryGetValue(selected, out var target))
+            return null;
+
+        return target.Position
+            + System.Numerics.Vector3.Transform(
+                new System.Numerics.Vector3(0f, 0f, 0.5f), target.Rotation);
+    }
+
     // ============================================================
     // Phase B.4b — outbound Use handler. Wires three input actions
     // (LMB click select, LMB-double-click select+use, R hotkey