pdf清晰度调整

src/components/PreviewPDF.vue

@@ -42,7 +42,7 @@ async function loadPage(pageNum) {
     loadingPages.value.push(pageNum)
     try {
       const page = await pdfDoc.getPage(pageNum);
-      const viewport = page.getViewport({ scale: 1 });
+      const viewport = page.getViewport({ scale: 4 });
       const canvas = document.getElementById(`pdfCanvas${pageNum-1}`)
       const context = canvas.getContext("2d");