fix: clear ONLYOFFICE internal cache after save + mtime-based download URL

renderer/onlyoffice-service.js

@@ -146,10 +146,11 @@ router.get('/:templateId/config', (req, res) => {
   const docKey = generateDocKey(templateId, fileMtime);
   const fileName = template.originalName || template.name + '.docx';
   
-  // Add cache-busting timestamp to the document URL so ONLYOFFICE
-  // always fetches the latest version from our backend
-  const cacheBuster = Date.now();
-  const documentUrl = `${BACKEND_PUBLIC_URL}/api/onlyoffice/${templateId}/download?cb=${cacheBuster}`;
+  // Add file mtime as cache-buster to the document URL so ONLYOFFICE
+  // always fetches the latest version from our backend.
+  // The mtime changes every time the file is saved, so the URL is
+  // different after each save, forcing ONLYOFFICE to re-download.
+  const documentUrl = `${BACKEND_PUBLIC_URL}/api/onlyoffice/${templateId}/download?mtime=${fileMtime}&cb=${Date.now()}`;
   const callbackUrl = `${BACKEND_PUBLIC_URL}/api/onlyoffice/${templateId}/callback`;
   
   const config = {
@@ -316,6 +317,17 @@ router.post('/:templateId/callback', async (req, res) => {
       
       console.log(`Template "${template.name}" updated successfully (${response.data.length} bytes)`);
       
+      // Clear ONLYOFFICE's internal document cache for this template
+      // so the next edit session fetches the fresh file
+      try {
+        const { execSync } = require('child_process');
+        execSync(`docker exec onlyoffice-server find /var/lib/onlyoffice/documentserver/App_Data/cache -name "cvtemplate_${templateId}*" -type d -exec rm -rf {} + 2>/dev/null || true`, { timeout: 5000 });
+        console.log('ONLYOFFICE cache cleared for template:', templateId);
+      } catch (cacheErr) {
+        // Non-fatal — cache will expire naturally
+        console.log('Cache clear skipped:', cacheErr.message.substring(0, 100));
+      }
+      
       // ONLYOFFICE expects a JSON response acknowledging the save
       return res.json({ 
         error: 0,