feat(app): WASDMove script (WASD camera-relative movement)

ScriptBehavior gains App() host access (Application injected via
ScriptRuntime), TryGet<T> and EntityBits for physics facade addressing.
WASDMove maps WASD to the editor camera's horizontal heading (UE
gameplay convention): dynamic bodies go through the physics velocity
facade preserving the vertical component (zeroing Y would cancel
gravity mid-fall), bodiless entities translate their transform directly.
Editor-mode key conflict is naturally avoided: RMB-held flight consumes
WASD, release hands keys to the script.

Engine/src/Core/Application.cpp

@@ -103,8 +103,9 @@ namespace Engine {
         // 物理调试图元 → 渲染侧（PhysicsDebugPass 每帧上传绘制）
         m_Renderer->SetPhysicsDebugSource(&m_Physics->GetDebugFrame());
 
-        // 脚本生命周期（对账式，组件增删/改名即时生效）
-        m_Scripts = CreateScope<Scripting::ScriptRuntime>(*m_Scene);
+        // 脚本生命周期（对账式，组件增删/改名即时生效）；this 注入脚本
+        // 上下文（Window/Renderer/Physics 门面）
+        m_Scripts = CreateScope<Scripting::ScriptRuntime>(*m_Scene, this);
 
         while (m_Running) {
             const auto frameStart = std::chrono::steady_clock::now();