TCPBuffer

Summary:
Adds a TCPBuffer implementation to tensor_engine, as a fallback example for RDMABuffer.

The main change from the original TCP-based buffer is that it uses ZMQ for communications to 1) decouple from Monarch's message passing system and 2) to mimic RDMABuffer's design, and showcase how other backends can be easily added

Differential Revision: D79588454

Author: allenwang28

python/monarch/_src/actor/actor_mesh.py

@@ -169,6 +169,9 @@ def __init__(
         self._shape = shape
         self._please_replace_me_actor_ids = actor_ids
 
+    def get_actor_id(self) -> ActorId:
+        return self._please_replace_me_actor_ids[0]
+
     @staticmethod
     def from_hyperactor_mesh(
         mailbox: Mailbox, hy_actor_mesh: PythonActorMesh, proc_mesh: "ProcMesh"