gpui: Improve window.prompt to support ESC with non-English cancel text on macOS (#29538)

Release Notes:

- N/A

----

The before version GPUI used `Cancel` for cancel text, if we use
non-English text (e.g.: "取消" in Chinese), then the press `Esc` to cancel
will not work.

So this PR to change it by use `PromptButton` to instead the `&str`,
then we can use `PromptButton::cancel("取消")` for the `Cancel` button.

Run `cargo run -p gpui --example window` to test.

---

Platform Test:

- [x] macOS
- [x] Windows
- [x] Linux (x11 and Wayland)

---------

Co-authored-by: Mikayla Maki <mikayla@zed.dev>
Co-authored-by: Mikayla Maki <mikayla.c.maki@gmail.com>

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

@@ -608,7 +608,7 @@ impl PlatformWindow for WindowsWindow {
         level: PromptLevel,
         msg: &str,
         detail: Option<&str>,
-        answers: &[&str],
+        answers: &[PromptButton],
     ) -> Option<Receiver<usize>> {
         let (done_tx, done_rx) = oneshot::channel();
         let msg = msg.to_string();
@@ -616,8 +616,8 @@ impl PlatformWindow for WindowsWindow {
             Some(info) => Some(info.to_string()),
             None => None,
         };
-        let answers = answers.iter().map(|s| s.to_string()).collect::<Vec<_>>();
         let handle = self.0.hwnd;
+        let answers = answers.to_vec();
         self.0
             .executor
             .spawn(async move {
@@ -653,9 +653,9 @@ impl PlatformWindow for WindowsWindow {
                     let mut button_id_map = Vec::with_capacity(answers.len());
                     let mut buttons = Vec::new();
                     let mut btn_encoded = Vec::new();
-                    for (index, btn_string) in answers.iter().enumerate() {
-                        let encoded = HSTRING::from(btn_string);
-                        let button_id = if btn_string == "Cancel" {
+                    for (index, btn) in answers.iter().enumerate() {
+                        let encoded = HSTRING::from(btn.label().as_ref());
+                        let button_id = if btn.is_cancel() {
                             IDCANCEL.0
                         } else {
                             index as i32 - 100