refactor: extraer campo sender en Agent para desacoplar envio de mensajes

Añade un campo `sender effects.MatrixSender` al struct Agent que reemplaza
las llamadas directas a `a.matrix` para enviar mensajes (sendReply, typing,
SendMarkdown en handleTaskEvent). En produccion, sender apunta al mismo
*matrix.Client. Esto permite inyectar un spy en tests sin requerir una
conexion real a Matrix.

El campo `a.matrix` se mantiene para operaciones que no son de envio
(SetPresence, Raw, etc.).

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

agents/handler.go

@@ -29,8 +29,8 @@ func (a *Agent) handleEvent(ctx context.Context, msgCtx decision.MessageContext,
 	a.roomCtx.Set(roomID)
 
 	if a.cfg.Personality.Behavior.TypingIndicator {
-		_ = a.matrix.SendTyping(ctx, roomID, true)
-		defer a.matrix.SendTyping(ctx, roomID, false)
+		_ = a.sender.SendTyping(ctx, roomID, true)
+		defer a.sender.SendTyping(ctx, roomID, false)
 	}
 
 	// ── Command flow ─────────────────────────────────────────────────
@@ -233,8 +233,8 @@ func (a *Agent) handleTaskEvent(ctx context.Context, msg bus.AgentMessage) {
 	a.roomCtx.Set(roomID)
 
 	if a.cfg.Personality.Behavior.TypingIndicator {
-		_ = a.matrix.SendTyping(ctx, roomID, true)
-		defer a.matrix.SendTyping(ctx, roomID, false)
+		_ = a.sender.SendTyping(ctx, roomID, true)
+		defer a.sender.SendTyping(ctx, roomID, false)
 	}
 
 	// Build a synthetic MessageContext from the task
@@ -261,7 +261,7 @@ func (a *Agent) handleTaskEvent(ctx context.Context, msg bus.AgentMessage) {
 	if rejected {
 		a.logger.Warn("orchestrated task rejected by sanitizer",
 			"task_id", task.TaskID, "sender", task.OriginalSender)
-		_ = a.matrix.SendMarkdown(ctx, roomID, "El mensaje fue rechazado por el filtro de seguridad.")
+		_ = a.sender.SendMarkdown(ctx, roomID, "El mensaje fue rechazado por el filtro de seguridad.")
 		return
 	}
 	msgCtx.Content = sanitized
@@ -294,7 +294,7 @@ func (a *Agent) handleTaskEvent(ctx context.Context, msg bus.AgentMessage) {
 	}
 
 	// Send reply to Matrix room
-	if sendErr := a.matrix.SendMarkdown(ctx, roomID, reply); sendErr != nil {
+	if sendErr := a.sender.SendMarkdown(ctx, roomID, reply); sendErr != nil {
 		a.logger.Error("failed to send orchestrated reply to Matrix", "err", sendErr)
 	}
 
@@ -321,9 +321,9 @@ func (a *Agent) handleTaskEvent(ctx context.Context, msg bus.AgentMessage) {
 // If threadID is non-empty, the reply is sent as part of that thread.
 func (a *Agent) sendReply(ctx context.Context, roomID, eventID, threadID, markdown string) error {
 	if threadID != "" {
-		return a.matrix.SendThreadMarkdown(ctx, roomID, threadID, eventID, markdown)
+		return a.sender.SendThreadMarkdown(ctx, roomID, threadID, eventID, markdown)
 	}
-	return a.matrix.SendReplyMarkdown(ctx, roomID, eventID, markdown)
+	return a.sender.SendReplyMarkdown(ctx, roomID, eventID, markdown)
 }
 
 // parseSeverity converts a config string to sanitize.Severity.

agents/runtime.go

@@ -49,6 +49,7 @@ type Agent struct {
 	rules       []decision.Rule
 	llm         coretypes.CompleteFunc // nil when no LLM configured (simple_bot)
 	matrix      *matrix.Client
+	sender      effects.MatrixSender // used by sendReply; same object as matrix in production
 	runner      *effects.Runner
 	listener    *matrix.Listener
 	toolReg     *tools.Registry
@@ -157,6 +158,7 @@ func New(cfg *config.AgentConfig, rules []decision.Rule, agentACL acl.ACL, logge
 		rules:                rules,
 		llm:                  llmFunc,
 		matrix:               matrixClient,
+		sender:               matrixClient,
 		runner:               runner,
 		toolReg:              toolReg,
 		logger:               logger,