Add #[track_caller] to gpui foreground executor spawn methods (#24103)

Use of this location info was added in #21758 to help with diagnosing
remote_server panics on drop of tasks on a different thread.

Release Notes:

- N/A

crates/gpui/src/window.rs

@@ -1307,6 +1307,7 @@ impl Window {
     /// Spawn the future returned by the given closure on the application thread pool.
     /// The closure is provided a handle to the current window and an `AsyncWindowContext` for
     /// use within your future.
+    #[track_caller]
     pub fn spawn<Fut, R>(&self, cx: &App, f: impl FnOnce(AsyncWindowContext) -> Fut) -> Task<R>
     where
         R: 'static,