feat(renderer): enable vulkan validation layers in debug builds

Configured InstanceCreateInfo to request the VK_LAYER_KHRONOS_validation layer and the VK_EXT_debug_utils extension when compiling in debug mode. This lays the foundation for wiring Vulkan debug callbacks to tracing.

crates/renderer/src/lib.rs

@@ -16,12 +16,22 @@ impl Renderer {
     pub fn new(required_extensions: &[*const c_char]) -> Result<Self, RendererError> {
         let entry = unsafe { Entry::load() }?;
 
+        let mut extensions: Vec<*const c_char> = required_extensions.to_vec();
+        let mut layers: Vec<*const c_char> = Vec::new();
+
+        #[cfg(debug_assertions)]
+        {
+            extensions.push(ash::ext::debug_utils::NAME.as_ptr());
+            layers.push(c"VK_LAYER_KHRONOS_validation".as_ptr());
+        }
+
         let app_info = vk::ApplicationInfo::default()
             .api_version(vk::API_VERSION_1_3);
 
         let create_info = vk::InstanceCreateInfo::default()
             .application_info(&app_info)
-            .enabled_extension_names(required_extensions);
+            .enabled_extension_names(&extensions)
+            .enabled_layer_names(&layers);
 
         let instance = unsafe { entry.create_instance(&create_info, None)? };