feat(toolbar): replace driver update count badge with a dot

apps/desktop/src/components/layout/AppToolbar.vue

@@ -385,9 +385,8 @@ const toolbarDropdownTriggerClass = `inline-flex h-8 items-center gap-1 rounded-
       <Button v-if="toolbarItems.driverManager" variant="ghost" size="sm" :class="[toolbarTextButtonClass, { 'bg-accent': showDriverStore }]" @click="emit('open-driver-store')">
         <Package class="h-3.5 w-3.5" />
         <span :class="toolbarTextLabelClass">{{ t("toolbar.driverManager") }}</span>
-        <span v-if="agentDriverUpdateCount > 0" class="ml-0.5 inline-flex h-4 min-w-4 items-center justify-center rounded-full bg-red-500 px-1 text-[10px] font-medium leading-none text-white" :aria-label="t('toolbar.updatableDriverCount')">
-          {{ agentDriverUpdateCount > 99 ? "99+" : agentDriverUpdateCount }}
-        </span>
+        <!-- 小圆点仅提示"有可更新驱动"，具体数量交给对话框内标签页红点展示，避免工具栏长期挂红数字。 -->
+        <span v-if="agentDriverUpdateCount > 0" class="ml-0.5 inline-block h-2 w-2 rounded-full bg-red-500" :aria-label="t('toolbar.updatableDriverCount')" :title="t('toolbar.updatableDriverCount')" />
       </Button>
 
       <LightDropdown