feat: desacoplar launcher del registro estatico de agentes

Introduce un registro global de reglas en agents/registry.go con
Register() y GetRules(). Cada paquete de agente se auto-registra
via init(), eliminando la necesidad de editar manualmente el map
rulesRegistry en cmd/launcher/main.go.

Cambios:
- agents/registry.go: nuevo registro global con sync.RWMutex
- agents/*/agent.go: cada agente llama agents.Register() en init()
- agents/_template/agent.go: placeholder AGENT_ID_PLACEHOLDER para scaffold
- cmd/launcher/main.go: elimina rulesRegistry, usa blank imports +
  agents.GetRules() para obtener reglas por agent ID

Patron: init() + blank import (estandar Go: database/sql, image codecs)

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

agents/_template/agent.go

@@ -1,8 +1,16 @@
 // Package _template es un agente plantilla (no lanzable).
 // Sirve como referencia canonica para crear nuevos agentes.
+// Al crear un nuevo agente, new-agent.sh reemplaza _template y AGENT_ID_PLACEHOLDER.
 package _template
 
-import "github.com/enmanuel/agents/pkg/decision"
+import (
+	"github.com/enmanuel/agents/agents"
+	"github.com/enmanuel/agents/pkg/decision"
+)
+
+func init() {
+	agents.Register("AGENT_ID_PLACEHOLDER", Rules)
+}
 
 // Rules devuelve las reglas de este agente (vacio para el template).
 func Rules() []decision.Rule {

agents/asistente-2/agent.go

@@ -3,9 +3,14 @@
 package asistente2
 
 import (
+	"github.com/enmanuel/agents/agents"
 	"github.com/enmanuel/agents/pkg/decision"
 )
 
+func init() {
+	agents.Register("asistente-2", Rules)
+}
+
 // Rules returns the decision rules for the asistente-2 bot.
 // Note: !help is now handled by the built-in command system.
 func Rules() []decision.Rule {

agents/assistant-bot/agent.go

@@ -3,9 +3,14 @@
 package assistant
 
 import (
+	"github.com/enmanuel/agents/agents"
 	"github.com/enmanuel/agents/pkg/decision"
 )
 
+func init() {
+	agents.Register("assistant-bot", Rules)
+}
+
 // Rules returns the decision rules for the assistant bot.
 // Note: !help is now handled by the built-in command system.
 func Rules() []decision.Rule {

agents/meteorologo/agent.go

@@ -3,9 +3,14 @@
 package meteorologo
 
 import (
+	"github.com/enmanuel/agents/agents"
 	"github.com/enmanuel/agents/pkg/decision"
 )
 
+func init() {
+	agents.Register("meteorologo", Rules)
+}
+
 // Rules returns the decision rules for the meteorologo bot.
 func Rules() []decision.Rule {
 	return []decision.Rule{

agents/registry.go

@@ -0,0 +1,61 @@
+// Package agents provides a global registry for agent rule factories.
+//
+// Each agent package self-registers via init() using Register.
+// The launcher retrieves rules via GetRules without importing agent
+// packages explicitly (only blank imports are needed).
+package agents
+
+import (
+	"sync"
+
+	"github.com/enmanuel/agents/pkg/decision"
+)
+
+// RulesFunc is a factory that returns the decision rules for an agent.
+type RulesFunc func() []decision.Rule
+
+var (
+	registryMu sync.RWMutex
+	registry   = make(map[string]RulesFunc)
+)
+
+// Register adds a rule factory for the given agent ID.
+// Intended to be called from init() in each agent package.
+// Panics if the same ID is registered twice (catches copy-paste errors early).
+func Register(id string, fn RulesFunc) {
+	registryMu.Lock()
+	defer registryMu.Unlock()
+
+	if _, exists := registry[id]; exists {
+		panic("agents.Register: duplicate agent id: " + id)
+	}
+	registry[id] = fn
+}
+
+// GetRules returns the rule factory for the given agent ID.
+// Returns nil if no rules are registered (the agent is command-only).
+func GetRules(id string) RulesFunc {
+	registryMu.RLock()
+	defer registryMu.RUnlock()
+	return registry[id]
+}
+
+// RegisteredIDs returns a sorted list of all registered agent IDs.
+// Useful for debugging and diagnostics.
+func RegisteredIDs() []string {
+	registryMu.RLock()
+	defer registryMu.RUnlock()
+
+	ids := make([]string, 0, len(registry))
+	for id := range registry {
+		ids = append(ids, id)
+	}
+	return ids
+}
+
+// resetRegistry clears all registrations (for testing only).
+func resetRegistry() {
+	registryMu.Lock()
+	defer registryMu.Unlock()
+	registry = make(map[string]RulesFunc)
+}

cmd/launcher/main.go

@@ -20,9 +20,6 @@ import (
 	"github.com/spf13/cobra"
 
 	"github.com/enmanuel/agents/agents"
-	assistantagent "github.com/enmanuel/agents/agents/assistant-bot"
-	asistente2agent "github.com/enmanuel/agents/agents/asistente-2"
-	meteorologoagent "github.com/enmanuel/agents/agents/meteorologo"
 	"github.com/enmanuel/agents/internal/config"
 	"github.com/enmanuel/agents/pkg/decision"
 	"github.com/enmanuel/agents/pkg/orchestration"
@@ -31,15 +28,12 @@ import (
 	agentlog "github.com/enmanuel/agents/shell/logger"
 	orchshell "github.com/enmanuel/agents/shell/orchestration"
 	shellsecurity "github.com/enmanuel/agents/shell/security"
-)
 
-// rulesRegistry maps agent IDs to their rule factories.
-// Add a new entry here when you create a new agent package.
-var rulesRegistry = map[string]func() []decision.Rule{
-	"assistant-bot": assistantagent.Rules,
-	"asistente-2":   asistente2agent.Rules,
-	"meteorologo":   meteorologoagent.Rules,
-}
+	// Blank imports: each agent self-registers its rules via init().
+	_ "github.com/enmanuel/agents/agents/assistant-bot"
+	_ "github.com/enmanuel/agents/agents/asistente-2"
+	_ "github.com/enmanuel/agents/agents/meteorologo"
+)
 
 func main() {
 	var (
@@ -289,10 +283,13 @@ func startOrchestrator(agentBus *bus.Bus, logger *slog.Logger) (*orchHandle, err
 	return &orchHandle{orchestrator: orch, cfg: cfg}, nil
 }
 
+// rulesFor retrieves the rule factory for the given agent ID from the
+// global registry (populated by init() in each agent package).
+// Returns nil if no rules are registered (command-only bot).
 func rulesFor(agentID string, logger *slog.Logger) []decision.Rule {
-	factory, ok := rulesRegistry[agentID]
-	if !ok {
-		logger.Warn("no rules registered for agent, using empty ruleset", "id", agentID)
+	factory := agents.GetRules(agentID)
+	if factory == nil {
+		logger.Warn("no rules registered for agent, using empty ruleset (command-only)", "id", agentID)
 		return nil
 	}
 	return factory()