feat: name export file with meaningful title instead of id (#379)

backend/config/contentDisposition.js

@@ -0,0 +1,16 @@
+export function toSafeFileName(fileName) {
+  const s = String(fileName ?? '')
+    // eslint-disable-next-line no-control-regex
+    .replace(/[\u0000-\u001F\u007F]/g, '')
+    .replace(/[<>:"/\\|?*]/g, '_')
+    .replace(/\s+/g, ' ')
+    .trim();
+
+  return s;
+}
+
+export function contentDisposition(filename) {
+  const fallback = filename.replace(/[^\x20-\x7E]/g, '_').replace(/"/g, "'");
+  const encoded = encodeURIComponent(filename);
+  return `attachment; filename="${fallback}"; filename*=UTF-8''${encoded}`;
+}