Reorganize directory layout: editor panels/, grouped shaders, drop stale header

- App/editor: move 7 panels into panels/ (Editor core stays at root)
- shaders/: group into pbr/ post/ debug/ env/ (runtime load paths updated)
- Delete outdated duplicate Engine/src/Renderer/VulkanAssetUploader.h

shaders/debug/debug_line.frag

@@ -0,0 +1,10 @@
+#version 450
+
+layout(location = 0) in vec4 inColor;
+layout(location = 0) out vec4 outColor;
+
+void main() {
+    // HDR 的 a = 窗口透过率语义（透明窗口与桌面合成）：调试图元
+    // 永远不透明（a=1），rgb 直写线性 HDR 值
+    outColor = vec4(inColor.rgb, 1.0);
+}