Fix PDF export font embedding and improve sync reliability

- Replace data URL loading with temporary HTML file to avoid URL length limits
- Embed font files as data URLs in print document CSS for offline rendering
- Add font asset registry for Merriweather, Crimson Pro, Roboto Serif, and Average
- Implement font file caching and blob-to-data-URL conversion
- Clean up temporary HTML file after PDF generation
- Fix sync to refresh notes after favorite status sync completes

src/components/NoteEditor.tsx

@@ -11,6 +11,7 @@ import {
 } from '../services/desktop';
 import {
   getNoteTitleFromContent,
+  loadPrintFontFaceCss,
   PrintExportPayload,
   sanitizeFileName,
 } from '../printExport';
@@ -268,6 +269,7 @@ export function NoteEditor({ note, onUpdateNote, onToggleFavorite, onUnsavedChan
         html: noteHtml,
         previewFont,
         previewFontSize,
+        previewFontFaceCss: await loadPrintFontFaceCss(previewFont),
       };
 
       await exportPdfDocument({