feat: mensajes progresivos en Matrix con ProgressReporter

Implementa la Fase 2 del issue 0036: mensajes de progreso en tiempo real
que muestran al usuario que herramientas esta usando el agente claude-code.

- SendMarkdownGetID en shell/matrix/client.go: envia mensaje y retorna
  el event ID para editarlo despues
- EditMessage en shell/matrix/client.go: edita un mensaje existente
  usando m.replace (m.relates_to con rel_type=m.replace)
- ProgressReporter en shell/effects/progress.go (NEW): recibe streaming
  events y actualiza un mensaje unico en Matrix mostrando el progreso
  (e.g. "🔧 Bash: ls -la" → "🔧 Read: file.go" → "✅ Completado")
- Rate limiter integrado: max 1 edit/segundo para no saturar el homeserver
- Conectado en devagents/handler.go: cuando provider=claude-code y
  streaming+show_tool_progress habilitados, crea ProgressReporter y
  pasa StreamFunc al CompletionRequest
- MatrixSender interface actualizada con los nuevos metodos
- 10 tests nuevos para ProgressReporter, todos los existentes pasan

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

devagents/handler.go

@@ -13,6 +13,7 @@ import (
 	"github.com/enmanuel/agents/pkg/sanitize"
 	"github.com/enmanuel/agents/shell/audit"
 	"github.com/enmanuel/agents/shell/bus"
+	"github.com/enmanuel/agents/shell/effects"
 )
 
 // handleEvent is called by the matrix Listener for each filtered incoming event.
@@ -184,14 +185,28 @@ func (a *Agent) executeActions(ctx context.Context, roomID string, msgCtx decisi
 			})
 			a.persistMessage(ctx, memKey, coretypes.RoleUser, msgCtx.Content)
 
-			reply, err := a.runLLM(ctx, msgCtx, memKey)
+			// Create ProgressReporter for claude-code streaming if enabled
+			var progress *effects.ProgressReporter
+			if a.isStreamingEnabled() {
+				progress = effects.NewProgressReporter(a.sender, roomID, a.logger)
+			}
+
+			reply, err := a.runLLM(ctx, msgCtx, memKey, progress)
 			if err != nil {
 				a.logger.Error("llm error", "err", err)
+				if progress != nil {
+					progress.Finalize("\u274c Error al procesar la solicitud.")
+				}
 				expanded = append(expanded, decision.Action{
 					Kind:  decision.ActionKindReply,
 					Reply: &decision.ReplyAction{Content: "Sorry, I encountered an error.", InReplyTo: msgCtx.EventID, ThreadID: msgCtx.ThreadID},
 				})
 			} else {
+				// If progress reporter was used, finalize it with a done indicator
+				if progress != nil && progress.EventID() != "" {
+					progress.Finalize("\u2705 *Completado*")
+				}
+
 				expanded = append(expanded, decision.Action{
 					Kind:  decision.ActionKindReply,
 					Reply: &decision.ReplyAction{Content: reply, InReplyTo: msgCtx.EventID, ThreadID: msgCtx.ThreadID},
@@ -295,7 +310,7 @@ func (a *Agent) handleTaskEvent(ctx context.Context, msg bus.AgentMessage) {
 		Role: coretypes.RoleUser, Content: msgCtx.Content,
 	})
 
-	reply, err := a.runLLM(ctx, msgCtx, roomID)
+	reply, err := a.runLLM(ctx, msgCtx, roomID, nil)
 
 	// Build the result to send back via bus
 	result := orchestration.TaskResult{
@@ -368,6 +383,14 @@ func (a *Agent) emitAudit(evt audit.Event) {
 	}
 }
 
+// isStreamingEnabled returns true when the agent uses claude-code provider
+// with streaming and show_tool_progress both enabled.
+func (a *Agent) isStreamingEnabled() bool {
+	return a.cfg.LLM.Primary.Provider == "claude-code" &&
+		a.cfg.LLM.Primary.ClaudeCode.Streaming &&
+		a.cfg.LLM.Primary.ClaudeCode.ShowToolProgress
+}
+
 // sanitizeInput runs prompt injection detection on the message content.
 // Returns the (possibly modified) content and true if the message should be rejected.
 func (a *Agent) sanitizeInput(content, roomID, senderID string) (string, bool) {