linux: Better GPU debugging (#14706)

Release Notes:

- linux: Added GPU information to `editor: Copy System Specs to
Clipboard`
- linux: Show a prominant warning before running under llvmpipe and
similar.

crates/gpui/src/platform/windows/window.rs

@@ -654,6 +654,10 @@ impl PlatformWindow for WindowsWindow {
     fn get_raw_handle(&self) -> HWND {
         self.0.hwnd
     }
+
+    fn gpu_specs(&self) -> Option<GPUSpecs> {
+        Some(self.0.state.borrow().renderer.gpu_specs())
+    }
 }
 
 #[implement(IDropTarget)]