fix(ie-shell): fix segfault on window close — drop gpu_renderer before window #77

Rust drops struct fields in declaration order. The GpuRenderer holds
a wgpu::Surface that references the Window, so it must be dropped
first. Reorder fields: gpu_renderer before window.

Author: thomasnemer

crates/ie-shell/src/app.rs

@@ -19,8 +19,10 @@ pub enum UserEvent {
 }
 
 pub struct Browser {
-    window: Option<Arc<Window>>,
+    // gpu_renderer MUST be before window — it holds a wgpu::Surface
+    // referencing the window, so it must drop first
     gpu_renderer: Option<ie_render::GpuRenderer>,
+    window: Option<Arc<Window>>,
     tab_manager: TabManager,
     bookmark_store: BookmarkStore,
     overlay: OverlayState,