fix(app): exit to prompt instead of font picker when pygame exits

When user presses Ctrl+C in pygame display, the pipeline mode now
returns to the command prompt instead of continuing to the font picker.

engine/app.py

@@ -1134,8 +1134,11 @@ def run_pipeline_mode(preset_name: str = "demo"):
             frame += 1
 
     except KeyboardInterrupt:
-        pass
+        pipeline.cleanup()
-    finally:
+        display.cleanup()
+        print("\n  \033[38;5;245mPipeline stopped\033[0m")
+        return  # Exit pipeline mode, not font picker
+
     pipeline.cleanup()
     display.cleanup()
     print("\n  \033[38;5;245mPipeline stopped\033[0m")