Hide PDF download button in user messages

사용자가 업로드한 PDF는 이미 갖고 있으므로 저장 버튼 불필요.
renderMarkdown/renderLinkButton에 hideDownload 옵션 추가,
유저 메시지 렌더링 시 적용. 미리보기 버튼은 유지.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web-ui/index.html

@@ -4735,7 +4735,7 @@ function renderChatMessages() {
       <div class="msg-avatar">${msg.role === 'user' ? 'U' : '<img src="cherry_logo.png" style="width:48px;height:48px;border-radius:6px">'}</div>
       <div class="msg-body">
         <div class="msg-role">${msg.role === 'user' ? 'You' : (msg.mode === 'agentic' ? 'CherryClaw (Agent)' : 'CherryClaw')}</div>
-        ${msg.role === 'ai' ? renderAssistantContent(msg.content) : `<div class="msg-content">${renderMarkdown(msg.display !== undefined ? msg.display : msg.content)}</div>`}
+        ${msg.role === 'ai' ? renderAssistantContent(msg.content) : `<div class="msg-content">${renderMarkdown(msg.display !== undefined ? msg.display : msg.content, { hideDownload: true })}</div>`}
         ${msg.role === 'ai' ? renderArtifacts(msg.artifacts) : ''}
         ${msg.role === 'ai' ? renderFileDownloads(msg.steps, msg.processEntries, msg.content) : ''}
         ${msg.role === 'ai' && msg.processEntries && msg.processEntries.length ? renderProcessPill(msg.processEntries) : ''}
@@ -8498,7 +8498,8 @@ function _normalizeFileUrl(url) {
   return url;
 }
 
-function _renderLinkButton(text, url) {
+function _renderLinkButton(text, url, opts) {
+  var hideDownload = opts && opts.hideDownload;
   url = _normalizeFileUrl(url);
   var fileExts = ['.pptx','.pdf','.xlsx','.xls','.docx','.doc','.zip','.csv','.mp4','.mp3'];
   var isDownload = fileExts.some(function(ext) { return text.toLowerCase().endsWith(ext); })
@@ -8523,7 +8524,7 @@ function _renderLinkButton(text, url) {
       + '<a href="' + url + '" target="_blank" rel="noopener" class="download-btn" title="새 탭에서 열기">'
       + '<span style="font-size:14px">📄</span> ' + text + '</a>'
       + '<button class="pptx-preview-btn" onclick="togglePdfEmbed(\'' + escHtml(url) + '\',\'' + pdfId + '\',this)">&#9664; 미리보기</button>'
-      + '<a href="' + url + '" onclick="downloadFile(event,this)" class="pptx-preview-btn" style="text-decoration:none">&#11015; 저장</a>'
+      + (hideDownload ? '' : '<a href="' + url + '" onclick="downloadFile(event,this)" class="pptx-preview-btn" style="text-decoration:none">&#11015; 저장</a>')
       + '</div>'
       + '<div id="' + pdfId + '" style="display:none">'
       + '<iframe style="width:100%;height:600px;border:1px solid var(--line);border-radius:8px" allowfullscreen></iframe>'
@@ -8661,7 +8662,7 @@ function toggleTxtEmbedBtn(btn) {
   }
 }
 
-function renderMarkdown(text) {
+function renderMarkdown(text, opts) {
   if (!text) return '';
 
   // Extract existing <img> tags before escaping so they survive escHtml()
@@ -8695,12 +8696,12 @@ function renderMarkdown(text) {
 
   // Links: [text](url) — render download links for file types as buttons, PPTX gets preview
   html = html.replace(/\[([^\]]+)\]\(([^)]+)\)/g, function(_, text, url) {
-    return _renderLinkButton(text, url);
+    return _renderLinkButton(text, url, opts);
   });
 
   // Bare /api/files/... URLs — auto-convert to download buttons even without markdown syntax
   html = html.replace(/(\s|^)(\/api\/files\/[^\s<"]+)/g, function(_, space, url) {
-    return space + _renderLinkButton(decodeURIComponent(url.split('/').pop() || 'download'), url);
+    return space + _renderLinkButton(decodeURIComponent(url.split('/').pop() || 'download'), url, opts);
   });
 
   // Bold