feat: Do not exit from default Python script

internal/orchestrator/app/generator/app_template/python/main.py

@@ -1,6 +1,15 @@
-def main():
-    print("Hello World!")
+import time
 
+from arduino.app_utils import App
 
-if __name__ == "__main__":
-    main()
+print("Hello world!")
+
+
+def loop():
+    """This function is called repeatedly by the App framework."""
+    # You can replace this with any code you want your App to run repeatedly.
+    time.sleep(10)
+
+
+# See: https://docs.arduino.cc/software/app-lab/tutorials/getting-started/#app-run
+App.run(user_loop=loop)

internal/orchestrator/app/generator/testdata/app-all.golden/python/main.py

@@ -1,6 +1,15 @@
-def main():
-    print("Hello World!")
+import time
 
+from arduino.app_utils import App
 
-if __name__ == "__main__":
-    main()
+print("Hello world!")
+
+
+def loop():
+    """This function is called repeatedly by the App framework."""
+    # You can replace this with any code you want your App to run repeatedly.
+    time.sleep(10)
+
+
+# See: https://docs.arduino.cc/software/app-lab/tutorials/getting-started/#app-run
+App.run(user_loop=loop)

internal/orchestrator/app/generator/testdata/app-no-sketch.golden/python/main.py

@@ -1,6 +1,15 @@
-def main():
-    print("Hello World!")
+import time
 
+from arduino.app_utils import App
 
-if __name__ == "__main__":
-    main()
+print("Hello world!")
+
+
+def loop():
+    """This function is called repeatedly by the App framework."""
+    # You can replace this with any code you want your App to run repeatedly.
+    time.sleep(10)
+
+
+# See: https://docs.arduino.cc/software/app-lab/tutorials/getting-started/#app-run
+App.run(user_loop=loop)