[前端+RAG] 修复PDF ArrayBuffer detached；修复阅读模式右侧空白(覆盖PyMuPDF固定宽度)

chat_web_front/src/views/reading/index.vue

@@ -460,7 +460,11 @@ const loadPdfFile = async () => {
       params: { fileId: selectedFile.value.fileId },
       responseType: 'arraybuffer'
     });
-    pdfData.value = resp.data;
+    // 复制 ArrayBuffer 避免被 Vue 响应式代理导致 detached
+    const src = resp.data as ArrayBuffer;
+    const copy = new ArrayBuffer(src.byteLength);
+    new Uint8Array(copy).set(new Uint8Array(src));
+    pdfData.value = copy;
   } catch (e: any) {
     pdfData.value = null;
     docHtml.value = '<p style="color:#999;text-align:center;margin-top:40px;">PDF 文件加载失败</p>';