Adds filtering to list agents request

Adds optional filtering parameters to the ListAgentsRequest.
This allows filtering agents by logged-in status and/or agent state,
improving the efficiency of agent listing operations.

Author: Braden Olsen

tcnapi/exile/gate/v2/public.proto

@@ -1277,9 +1277,11 @@ message UpdateAgentStatusResponse {}
 
 /**
  * Request message for listing agents.
- * Empty message as no parameters are needed.
  */
-message ListAgentsRequest {}
+message ListAgentsRequest {
+  optional bool logged_in = 1; // optional filter to return only logged-in agent
+  optional AgentState state = 2; // optional filter to return only agents in the specified state
+}
 
 /**
  * Response message for listing agents (streamed).