feat: add message queue for sequential run processing (#501)

Allow sending multiple messages while a run is active. Messages are
queued on the server and processed sequentially after each run
completes. Each completed assistant message triggers speech playback
independently, and the UI shows queue status with a badge indicator.

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

packages/client/src/i18n/locales/es.ts

@@ -117,6 +117,8 @@ export default {
     emptyState: 'Inicia una conversacion con Hermes Agent',
     inputPlaceholder: 'Escribe un mensaje... (Enter para enviar, Shift+Enter para nueva linea)',
     attachFiles: 'Adjuntar archivos',
+    messageQueue: 'Cola de mensajes',
+    removeQueuedMessage: 'Quitar mensaje de la cola',
     stop: 'Detener',
     send: 'Enviar',
     contextUsed: 'Contexto utilizado:',