refactor(text_rendering): 优化文本渲染示例并更新窗口配置

- 删除冗余注释和临时文件note.txt
- 更新窗口标题为中文并修改后端为SDL2
- 简化相机服务配置方式

examples/image_display/assets/images/note.txt

@@ -1,4 +0,0 @@
-请将 1.jpg 图片复制到此目录，并重命名为 demo.jpg
-
-源文件位置: C:\Users\soulcoco\Desktop\Extra2D\1.jpg
-目标文件位置: C:\Users\soulcoco\Desktop\Extra2D\examples\image_display\assets\images\demo.jpg

examples/text_rendering/main.cpp

@@ -57,7 +57,6 @@ public:
     float y = 100.0f;
     float x = 100.0f;
 
-    // 渲染标题（自动批处理，无需手动调用 begin/end）
     renderText(renderer, "Extra2D Text Rendering Demo", x, y,
                Color(1.0f, 0.8f, 0.2f, 1.0f));
     y += font_->getLineHeight() * 2;
@@ -91,8 +90,6 @@ public:
     // 渲染操作提示
     renderText(renderer, "Press ESC to exit", x, y,
                Color(0.5f, 0.5f, 0.5f, 1.0f));
-
-    // 注意：无需手动调用 renderer.endSpriteBatch()，帧结束时会自动刷新
   }
 
   void setRenderer(RenderBackend *renderer) { renderer_ = renderer; }
@@ -120,9 +117,9 @@ int main(int argc, char *argv[]) {
   app.use<WindowModule>([](auto &cfg) {
     cfg.w = 1280;
     cfg.h = 720;
-    cfg.title = "Extra2D Text Rendering Demo";
+    cfg.title = "Extra2D 文字显示示例";
     cfg.priority = 0;
-    cfg.backend = "glfw";
+    cfg.backend = "sdl2";
   });
 
   app.use<RenderModule>([](auto &cfg) { cfg.priority = 10; });
@@ -167,11 +164,11 @@ int main(int argc, char *argv[]) {
   // 配置相机
   auto cameraService = ServiceLocator::instance().getService<ICameraService>();
   if (cameraService && win) {
-    ViewportConfig vpConfig;
-    vpConfig.logicWidth = static_cast<float>(win->width());
-    vpConfig.logicHeight = static_cast<float>(win->height());
-    vpConfig.mode = ViewportMode::AspectRatio;
-    cameraService->setViewportConfig(vpConfig);
+    cameraService->setViewportConfig([&](auto &cfg) {
+      cfg.logicWidth = static_cast<float>(win->width());
+      cfg.logicHeight = static_cast<float>(win->height());
+      cfg.mode = ViewportMode::AspectRatio;
+    });
     cameraService->updateViewport(win->width(), win->height());
     cameraService->applyViewportAdapter();
   }