feat: implementar tipo Robot como runtime ligero para bots command-only

Introduce la separacion Robot vs Agent en el sistema:

- agents/types.go: interfaz Runner comun (Run, Stop, Done, RegisterCommand)
  que tanto Agent como Robot satisfacen
- agents/robot.go: struct Robot — runtime minimo que solo conecta a Matrix
  y despacha comandos. Sin LLM, reglas, memoria, knowledge, skills ni tools.
  Mensajes normales se ignoran silenciosamente
- internal/config/schema.go: campo Type en AgentMeta ("agent"|"robot")
- cmd/launcher: usa Runner interface para manejar ambos tipos uniformemente.
  Si cfg.Agent.Type == "robot" crea NewRobot en vez de New (tanto en
  arranque como en hot-reload)
- agents/_template_robot/config.yaml: plantilla minima (~55 lineas) para
  robots command-only

El Robot soporta built-in commands reducidos (help, ping, status, info,
version) y comandos custom via RegisterCommand. No incluye tools, tool,
clear ni prompts ya que no tiene LLM ni memoria.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cmd/launcher/main.go

@@ -158,8 +158,6 @@ func main() {
 					continue
 				}
 
-				rules := rulesFor(cfg.Agent.ID, logger)
-
 				// Per-agent logger → writes to logs/<agent-id>/YYYY-MM-DD.jsonl
 				agentLogger, agentCleanup, aErr := agentlog.NewAgentLogger(agentlog.LoggerConfig{
 					BaseDir: logDir,
@@ -172,41 +170,59 @@ func main() {
 					agentCleanup = func() {}
 				}
 
-				// Resolve centralized ACL for this agent
-				agentACL := pksecurity.ResolveACL(cfg.Agent.ID, deps.secPolicy)
-				agentLogger.Debug("resolved acl for agent",
-					"agent", cfg.Agent.ID,
-					"acl_empty", agentACL.Empty(),
-				)
+				// Branch: robot (command-only, lightweight) vs agent (full runtime).
+				var runner agents.Runner
 
-				a, err := agents.New(cfg, rules, agentACL, agentLogger)
-				if err != nil {
-					logger.Error("failed to create agent", "id", cfg.Agent.ID, "err", err)
-					agentCleanup()
-					continue
-				}
+				if cfg.Agent.Type == "robot" {
+					robot, rErr := agents.NewRobot(cfg, agentLogger)
+					if rErr != nil {
+						logger.Error("failed to create robot", "id", cfg.Agent.ID, "err", rErr)
+						agentCleanup()
+						continue
+					}
+					runner = robot
+					agentLogger.Info("created robot", "id", cfg.Agent.ID)
+				} else {
+					rules := rulesFor(cfg.Agent.ID, logger)
 
-				// Connect agent to bus for orchestration
-				a.SetBus(agentBus)
+					// Resolve centralized ACL for this agent
+					agentACL := pksecurity.ResolveACL(cfg.Agent.ID, deps.secPolicy)
+					agentLogger.Debug("resolved acl for agent",
+						"agent", cfg.Agent.ID,
+						"acl_empty", agentACL.Empty(),
+					)
 
-				// If orchestrator is active, wire interceptor and membership notify
-				if orch != nil {
-					a.SetInterceptor(orch.orchestrator.Intercept)
-					a.SetMembershipNotify(orch.orchestrator.NotifyMembership)
+					a, cErr := agents.New(cfg, rules, agentACL, agentLogger)
+					if cErr != nil {
+						logger.Error("failed to create agent", "id", cfg.Agent.ID, "err", cErr)
+						agentCleanup()
+						continue
+					}
 
-					orch.orchestrator.RegisterParticipant(orchestration.ParticipantInfo{
-						ID:           cfg.Agent.ID,
-						MatrixUserID: cfg.Matrix.UserID,
-						Description:  cfg.Agent.Description,
-						Capabilities: cfg.Agent.Tags,
-					})
+					// Connect agent to bus for orchestration
+					a.SetBus(agentBus)
 
-					// Grab the first available Matrix client for room scanning
-					scannerOnce.set(a.RawMatrixClient())
+					// If orchestrator is active, wire interceptor and membership notify
+					if orch != nil {
+						a.SetInterceptor(orch.orchestrator.Intercept)
+						a.SetMembershipNotify(orch.orchestrator.NotifyMembership)
+
+						orch.orchestrator.RegisterParticipant(orchestration.ParticipantInfo{
+							ID:           cfg.Agent.ID,
+							MatrixUserID: cfg.Matrix.UserID,
+							Description:  cfg.Agent.Description,
+							Capabilities: cfg.Agent.Tags,
+						})
+
+						// Grab the first available Matrix client for room scanning
+						scannerOnce.set(a.RawMatrixClient())
+					}
+
+					runner = a
 				}
 
 				registry.register(&runningAgent{
-					agent:      a,
+					runner:     runner,
 					cfg:        cfg,
 					cfgPath:    path,
 					logger:     agentLogger,