Quit on window close when the app has no event callback

Without yasl_app_desc.event, a close request had nowhere to go and the
window stayed open. The runner now stops instead, so hello drops its
event callback.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/yasl/app.h b/include/yasl/app.h
index 79b2519..bf6de9c 100644
--- a/include/yasl/app.h
+++ b/include/yasl/app.h
@@ -166,7 +166,8 @@ struct yasl_app_desc {
      * Unified event handler for input, window and user events, in arrival order.
      * Event payloads and borrowed strings are valid for the duration of the callback.
      * INPUT_RESET has no payload and requires clearing held application input.
-     * Return YASL_APP_CONTINUE or YASL_APP_QUIT.
+     * Return YASL_APP_CONTINUE or YASL_APP_QUIT. Optional; without it, a
+     * WINDOW_CLOSE request on any window stops yasl_run().
      */
     enum yasl_app_result (*event)(void *ud, const struct yasl_event *ev);