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- Delete outdated duplicate Engine/src/Renderer/VulkanAssetUploader.h

Engine/src/Renderer/IblGenerator.cpp

@@ -74,7 +74,7 @@ namespace Engine
         m_LutLayout = descriptors.CreatePipelineLayout(
             {m_LutSetLayout}, 0, vk::ShaderStageFlagBits::eCompute);
 
-        const std::string dir = "shaders/";
+        const std::string dir = "shaders/env/";
         m_ToCubeShader = shaders.CreateFromFile(
             dir + "ibl_equirect_to_cube.comp.spv",
             vk::ShaderStageFlagBits::eCompute,