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/components/hermes/chat/MessageItem.vue

@@ -370,10 +370,13 @@ function handleSpeechToggle() {
     return
   }
   const content = props.message.content || ''
+  speech.toggle(props.message.id, content, getSpeechOptions())
+}
 
+function getSpeechOptions() {
   // 尝试获取男声语音包
   const allVoices = speech.getAllVoices()
-  let maleVoice = null
+  let maleVoice: SpeechSynthesisVoice | null = null
 
   // 查找可能的男声语音包
   for (const voice of allVoices) {
@@ -394,11 +397,11 @@ function handleSpeechToggle() {
   }
 
   // 快速男声：语速快、音调低
-  speech.toggle(props.message.id, content, {
+  return {
     pitch: 0.5,   // 低沉
     rate: 1.2,    // 快速
     voice: maleVoice || undefined, // 使用男声，如果没有就用默认
-  })
+  }
 }
 
 // 监听自动播放事件
@@ -408,7 +411,7 @@ onMounted(() => {
   autoPlayHandler = (e: Event) => {
     const customEvent = e as CustomEvent<{ messageId: string; content: string }>
     if (customEvent.detail.messageId === props.message.id && canPlaySpeech.value) {
-      handleSpeechToggle()
+      speech.enqueue(props.message.id, customEvent.detail.content || props.message.content || '', getSpeechOptions())
     }
   }
   window.addEventListener('auto-play-speech', autoPlayHandler)