feat(mcp): emit channel events for process start/stop/kill

process.start on successful spawn, process.exit on stop/kill.
Events include process ID, PID, command, and signal type.

Co-Authored-By: Virgil <virgil@lethean.io>

pkg/mcp/tools_process.go

@@ -194,13 +194,17 @@ func (s *Service) processStart(ctx context.Context, req *mcp.CallToolRequest, in
 	}
 
 	info := proc.Info()
-	return nil, ProcessStartOutput{
+	output := ProcessStartOutput{
 		ID:        proc.ID,
 		PID:       info.PID,
 		Command:   proc.Command,
 		Args:      proc.Args,
 		StartedAt: proc.StartedAt,
-	}, nil
+	}
+	s.ChannelSend(ctx, "process.start", map[string]any{
+		"id": output.ID, "pid": output.PID, "command": output.Command,
+	})
+	return nil, output, nil
 }
 
 // processStop handles the process_stop tool call.
@@ -224,6 +228,7 @@ func (s *Service) processStop(ctx context.Context, req *mcp.CallToolRequest, inp
 		return nil, ProcessStopOutput{}, log.E("processStop", "failed to stop process", err)
 	}
 
+	s.ChannelSend(ctx, "process.exit", map[string]any{"id": input.ID, "signal": "stop"})
 	return nil, ProcessStopOutput{
 		ID:      input.ID,
 		Success: true,
@@ -244,6 +249,7 @@ func (s *Service) processKill(ctx context.Context, req *mcp.CallToolRequest, inp
 		return nil, ProcessKillOutput{}, log.E("processKill", "failed to kill process", err)
 	}
 
+	s.ChannelSend(ctx, "process.exit", map[string]any{"id": input.ID, "signal": "kill"})
 	return nil, ProcessKillOutput{
 		ID:      input.ID,
 		Success: true,