[ray_client] actors v0 (#12388)

src/ray/protobuf/ray_client.proto

@@ -30,10 +30,16 @@ message Arg {
 }
 
 message ClientTask {
-  // Optionally Provided Task Name
-  string name = 1;
-  bytes payload_id = 2;
-  repeated Arg args = 3;
+  enum RemoteExecType {
+    FUNCTION = 0;
+    ACTOR = 1;
+    METHOD = 2;
+    STATIC_METHOD = 3;
+  }
+  RemoteExecType type = 1;
+  string name = 2;
+  bytes payload_id = 3;
+  repeated Arg args = 4;
 }
 
 message ClientTaskTicket {