feat: 优化UI，增加主页面空间

src/components/common/Sidebar.vue

@@ -194,7 +194,7 @@ function getSessionAvatar(session: AnalysisSession): string | null {
     class="flex h-full flex-col border-r border-gray-200/50 transition-all duration-300 ease-in-out dark:border-gray-800/50"
     :class="[isCollapsed ? 'w-20' : 'w-72', isHomePage ? '' : 'bg-gray-50 dark:bg-gray-900']"
   >
-    <div class="flex flex-col p-4 pt-8">
+    <div class="flex flex-col p-4 pt-5">
       <!-- Header -->
       <div
         class="mb-2 flex items-center"

src/components/layout/PageHeader.vue

@@ -15,9 +15,9 @@ defineProps<{
 
 <template>
   <div class="relative border-b border-gray-200/50 px-6 pb-2 dark:border-gray-800/50">
-    <!-- 拖拽区域 - 仅覆盖顶部区域 (包含上方 padding 的 32px + 头部内部 16px) -->
+    <!-- 拖拽区域 - 仅覆盖顶部区域 (包含上方 padding 的 16px + 头部内部 16px) -->
     <!-- 这样既保证了顶部可以拖拽，又不会遮挡 Header 内部的按钮和交互元素 -->
-    <div class="absolute -top-8 left-0 right-0 h-12 z-50" style="-webkit-app-region: drag" />
+    <div class="absolute -top-4 left-0 right-0 h-8 z-50" style="-webkit-app-region: drag" />
 
     <!-- 标题区域 -->
     <div class="flex items-center justify-between">

src/pages/group-chat/index.vue

@@ -186,7 +186,7 @@ onMounted(() => {
 </script>
 
 <template>
-  <div class="flex h-full flex-col bg-white pt-8 dark:bg-gray-900">
+  <div class="flex h-full flex-col bg-white pt-4 dark:bg-gray-900">
     <!-- Loading State -->
     <LoadingState v-if="isInitialLoad" variant="page" :text="t('analysis.groupChat.loading')" />
 

src/pages/home/index.vue

@@ -40,7 +40,7 @@ const features = computed(() => [
 </script>
 
 <template>
-  <div class="relative flex h-full w-full overflow-hidden pt-8">
+  <div class="relative flex h-full w-full overflow-hidden pt-4">
     <!-- Content Container -->
     <div class="relative h-full w-full overflow-y-auto">
       <div class="flex min-h-full w-full flex-col items-center justify-center px-4 py-12">

src/pages/manage/index.vue

@@ -7,7 +7,7 @@ const { t } = useI18n()
 </script>
 
 <template>
-  <div class="relative z-0 flex h-full flex-col bg-white pt-8 dark:bg-[var(--color-page-dark)]">
+  <div class="relative z-0 flex h-full flex-col bg-white pt-4 dark:bg-[var(--color-page-dark)]">
     <!-- Header -->
     <PageHeader
       :title="t('tools.title')"

src/pages/private-chat/index.vue

@@ -195,7 +195,7 @@ onMounted(() => {
 </script>
 
 <template>
-  <div class="flex h-full flex-col bg-white pt-8 dark:bg-gray-900">
+  <div class="flex h-full flex-col bg-white pt-4 dark:bg-gray-900">
     <!-- Loading State -->
     <LoadingState v-if="isInitialLoad" variant="page" :text="t('analysis.privateChat.loading')" />