Fix 3: optimize shutdown times

src/app/mod.rs

@@ -2139,6 +2139,16 @@ pub fn run() -> iced::Result {
     .run()
 }
 
+impl Drop for OpenCADStudio {
+    fn drop(&mut self) {
+        // Kill plugin runner processes as soon as the application state is
+        // dropped, instead of waiting for the thread-local manager destructor.
+        // This makes host shutdown deterministic and fast on every exit path.
+        #[cfg(not(target_arch = "wasm32"))]
+        crate::plugin::external::shutdown_plugins();
+    }
+}
+
 /// Single-window entry for the web (wasm) build. Uses `iced::application`
 /// instead of `iced::daemon`: the browser canvas is the only window, so the
 /// main-window view is rendered directly and the manager/dialog windows are

src/plugin/external.rs

@@ -221,7 +221,7 @@ fn parse_string_array(s: &str) -> Vec<String> {
 // ── Runtime loading (desktop only) ──────────────────────────────────────────
 
 #[cfg(not(target_arch = "wasm32"))]
-pub(crate) use loader::with_manager;
+pub(crate) use loader::{shutdown_plugins, with_manager};
 
 #[cfg(all(not(target_arch = "wasm32"), not(test)))]
 pub(crate) use loader::{load_at_startup, loaded_ids};
@@ -285,6 +285,15 @@ mod loader {
         })
     }
 
+    /// Eagerly shut down all plugin runner processes.
+    pub fn shutdown_plugins() {
+        MANAGER.with(|m| {
+            if let Some(mut manager) = m.borrow_mut().take() {
+                manager.shutdown_all();
+            }
+        });
+    }
+
     /// Path to the native library beside `plugin.toml`, if any.
     fn lib_file(dir: &Path) -> Option<PathBuf> {
         let ext = lib_extension();