Add Stop button to cancel running video generation

Wrap Generate Video button in a Row with a Stop button.
Capture click event and use cancels= to abort the running task.

app.py

@@ -710,7 +710,9 @@ with gr.Blocks(theme=gr.themes.Soft(), css=CSS, delete_cache=(3600, 3700)) as de
                 safety_checker_input = gr.Checkbox(label="Enable Safety Filter", value=True, info="Prevents unrequested sensitive or explicit content.")
                 play_result_video = gr.Checkbox(label="Display result", value=True, interactive=True)
 
-            generate_button = gr.Button("Generate Video", variant="primary")
+            with gr.Row():
+                generate_button = gr.Button("Generate Video", variant="primary", scale=4)
+                stop_button = gr.Button("⏹ Stop", variant="stop", scale=1)
 
         with gr.Column():
             # ASSIGNED elem_id="generated-video" so JS can find it
@@ -732,12 +734,20 @@ with gr.Blocks(theme=gr.themes.Soft(), css=CSS, delete_cache=(3600, 3700)) as de
         play_result_video, safe_mode_checkbox, safety_checker_input
     ]
     
-    generate_button.click(
-        fn=generate_video, 
-        inputs=ui_inputs, 
+    generate_event = generate_button.click(
+        fn=generate_video,
+        inputs=ui_inputs,
         outputs=[video_output, file_output, seed_input]
     )
-    
+
+    # Stop button: cancels the currently-running generate_video event.
+    stop_button.click(
+        fn=None,
+        inputs=None,
+        outputs=None,
+        cancels=[generate_event],
+    )
+
     # --- Frame Grabbing Events ---
     # 1. Click button -> JS runs -> puts time in hidden number box
     grab_frame_btn.click(