fix(build): 修复 v0.5.0-beta 前端编译错误

跑 npm run build 验收时发现 2 个前端项目编译失败(vue-tsc 报错),修复 4 处:

frontend-h5:
- src/components/chat/InputBox.vue:185 多余右括号
  computed(() => inputText.value.length))  ->  computed(() => inputText.value.length)
- src/components/chat/MessageList.vue:134 pollMessages 调用签名错
  pollMessages(convId, afterMessageId)   ->  pollMessages(afterMessageId)
  (api/message.ts:71 签名只接 1 个 afterMessageId 参数,endpoint 走 current 不需要 convId)

frontend-agent:
- src/components/chat/InputBox.vue 4 处错
  L91/234/292 conversationStore.loading 不存在(store 暴露的是 loadingMessages)
                     -> conversationStore.loadingMessages
  L136 import onUnmounted 死引用,移除

components.d.ts: 触发 unplugin-vue-components 重新生成 6 行(新组件类型)

验证:
- frontend-h5: vue-tsc 0 错,417 modules transformed, dist/ 生成
- frontend-agent: vue-tsc 0 错,1750 modules transformed, dist/ 生成

不影响业务逻辑,纯 build fix。

frontend-h5/src/components/chat/InputBox.vue

@@ -182,7 +182,7 @@ const showScreenshotEditor = ref(false)
 let screenshotCanvas: HTMLCanvasElement | null = null
 
 /** 当前字符数 */
-const charCount = computed(() => inputText.value.length))
+const charCount = computed(() => inputText.value.length)
 
 /** 是否可以发送消息 */
 const canSend = computed(() => {

frontend-h5/src/components/chat/MessageList.vue

@@ -131,7 +131,7 @@ async function fetchNewMessages(): Promise<void> {
     const lastMsg = messages.value[messages.value.length - 1]
     const afterMessageId = lastMsg?.message_id
 
-    const newMessages = await pollMessages(convId, afterMessageId)
+    const newMessages = await pollMessages(afterMessageId)
 
     if (newMessages && newMessages.length > 0) {
       // 添加新消息到列表