Move endpoint calling event upstream (#2165)

Summary:
Pull Request resolved: #2165

This is more honest about when a call/broadcast is actually being initiated

Reviewed By: moonli

Differential Revision: D89411458

fbshipit-source-id: 352489df799226d4d20df6f93ee0d5e97cf54539

Author: thomasywang

python/monarch/_src/actor/actor_mesh.py

@@ -595,7 +595,6 @@ def _send(
                 ),
                 buffer,
             )
-            instant_event(f"sending {self._get_method_name()} message")
             self._actor_mesh.cast(
                 message, selection, context().actor_instance._as_rust()
             )

python/monarch/_src/actor/endpoint.py

@@ -275,6 +275,7 @@ def call(self, *args: P.args, **kwargs: P.kwargs) -> "Future[ValueMesh[R]]":
         start_time: int = time.monotonic_ns()
         # Track throughput at method entry
         method_name: str = self._get_method_name()
+        instant_event(f"calling {method_name} message")
         endpoint_call_throughput_counter.add(1, attributes={"method": method_name})
         p, unranked = self._port()
         r: RankedPortReceiver[R] = unranked.ranked()
@@ -354,6 +355,7 @@ def broadcast(self, *args: P.args, **kwargs: P.kwargs) -> None:
         from monarch._src.actor.actor_mesh import send
 
         method_name: str = self._get_method_name()
+        instant_event(f"broadcasting {method_name} message")
         attributes = {
             "method": method_name,
             "actor_count": 0,  # broadcast doesn't track specific count