feat(export): tailor content batch dialog and widen layout menu

src/pages/ExportPage.scss

@@ -143,7 +143,9 @@
     position: absolute;
     top: calc(100% + 6px);
     left: 0;
-    right: 0;
+    right: auto;
+    width: clamp(300px, 36vw, 420px);
+    max-width: calc(100vw - 40px);
     background: var(--bg-primary);
     border: 1px solid var(--border-color);
     border-radius: 12px;
@@ -1453,6 +1455,13 @@
   gap: 6px;
 }
 
+.format-note {
+  margin: 0 0 8px;
+  font-size: 12px;
+  line-height: 1.45;
+  color: var(--text-secondary);
+}
+
 .format-card {
   width: 100%;
   min-height: 0;

src/pages/ExportPage.tsx

@@ -1487,6 +1487,11 @@ function ExportPage() {
       if (payload.scope === 'content' && payload.contentType) {
         if (payload.contentType === 'text') {
           next.exportMedia = false
+          next.exportImages = false
+          next.exportVoices = false
+          next.exportVideos = false
+          next.exportEmojis = false
+          next.exportAvatars = true
         } else {
           next.exportMedia = true
           next.exportImages = payload.contentType === 'image'
@@ -1536,6 +1541,7 @@ function ExportPage() {
       if (contentType === 'text') {
         return {
           ...base,
+          exportAvatars: true,
           exportMedia: false,
           exportImages: false,
           exportVoices: false,
@@ -2365,6 +2371,10 @@ function ExportPage() {
   const formatCandidateOptions = exportDialog.scope === 'sns'
     ? formatOptions.filter(option => option.value === 'html' || option.value === 'json')
     : formatOptions
+  const isContentScopeDialog = exportDialog.scope === 'content'
+  const isContentTextDialog = isContentScopeDialog && exportDialog.contentType === 'text'
+  const shouldShowFormatSection = !isContentScopeDialog || isContentTextDialog
+  const shouldShowMediaSection = !isContentScopeDialog
   const isTabCountComputing = isSharedTabCountsLoading && !isSharedTabCountsReady
   const isSessionCardStatsLoading = isBaseConfigLoading || (isSharedTabCountsLoading && !isSharedTabCountsReady)
   const isSnsCardStatsLoading = !hasSeededSnsStats
@@ -2948,8 +2958,12 @@ function ExportPage() {
                 </div>
               </div>
 
+              {shouldShowFormatSection && (
                 <div className="dialog-section">
                   <h4>对话文本导出格式选择</h4>
+                  {isContentTextDialog && (
+                    <div className="format-note">说明：此模式默认导出头像，不导出图片、语音、视频、表情包等媒体内容。</div>
+                  )}
                   <div className="format-grid">
                     {formatCandidateOptions.map(option => (
                       <button
@@ -2963,6 +2977,7 @@ function ExportPage() {
                     ))}
                   </div>
                 </div>
+              )}
 
               <div className="dialog-section">
                 <h4>时间范围</h4>
@@ -3018,6 +3033,7 @@ function ExportPage() {
                 )}
               </div>
 
+              {shouldShowMediaSection && (
                 <div className="dialog-section">
                   <h4>媒体与头像</h4>
                   <div className="media-check-grid">
@@ -3029,6 +3045,7 @@ function ExportPage() {
                     <label><input type="checkbox" checked={options.exportAvatars} onChange={event => setOptions(prev => ({ ...prev, exportAvatars: event.target.checked }))} /> 导出头像</label>
                   </div>
                 </div>
+              )}
 
               <div className="dialog-section">
                 <h4>发送者名称显示</h4>