修复 Unity 编译错误：变量冲突、DroneWave.DroneType 不存在、nullable 警告

- SimulationBootstrap: scenario 变量名冲突 → sc
- ManagerVerification: DroneWave.DroneType → Target (DroneWave 无此属性)
- ReportManager: string? → 拆为两个重载避免 nullable annotation 警告

src/Unity/Assets/Scripts/Managers/ManagerVerification.cs

@@ -56,7 +56,7 @@ namespace CounterDrone.Unity
             var droneGroup = new DroneWave
             {
                 WaveId = "default",
-                DroneType = detail.Targets[0].DroneType,
+                Target = detail.Targets[0],
                 Route = detail.Routes[0],
                 Waypoints = detail.WaypointGroups["default"],
             };

src/Unity/Assets/Scripts/Managers/ReportManager.cs

@@ -33,12 +33,17 @@ namespace CounterDrone.Unity
         public PagedResult<SimulationReport> Search(string kw, string from, string to, int page, int size)
             => _service.SearchReports(kw, from, to, page, size);
 
-        public string Export(string reportId, string? outputDir = null)
+        public string Export(string reportId, string outputDir)
         {
             var dir = outputDir ?? System.IO.Path.Combine(_paths.GetDataRoot(), "reports");
             return _service.ExportToFile(reportId, dir);
         }
 
+        public string Export(string reportId)
+        {
+            return Export(reportId, System.IO.Path.Combine(_paths.GetDataRoot(), "reports"));
+        }
+
         [ContextMenu("Verify")]
         void Verify()
         {

src/Unity/Assets/Scripts/Managers/SimulationBootstrap.cs

@@ -66,8 +66,8 @@ namespace CounterDrone.Unity
                 // 方式2：用 DefaultData 预设组装自定义想定
                 var defaults = DefaultData.Load(paths);
 
-                var scenario = scenario.CreateScenario("Unity Demo", "");
-                scenarioId = scenario.Id;
+                var sc = scenario.CreateScenario("Unity Demo", "");
+                scenarioId = sc.Id;
 
                 scenario.SaveScene(scenarioId, defaults.Environments.First(w => w.Id == "sunny-calm").ToCombatScene());
                 scenario.SaveTarget(scenarioId, defaults.Drones.First(p => p.Id == "shahed").ToDroneProfile());