Add streaming bulk ENEX migration tool and normalize attachment paths

src/lib/storage.ts

@@ -54,7 +54,8 @@ export async function saveAttachmentBuffer(
 
 export function getFullAttachmentPath(storagePath: string): string {
   const baseDir = getAttachmentsDir();
-  const resolved = path.resolve(baseDir, storagePath);
+  const normalizedStoragePath = storagePath.replace(/\\/g, '/');
+  const resolved = path.resolve(baseDir, normalizedStoragePath);
   if (!resolved.startsWith(path.resolve(baseDir))) {
     throw new Error('Invalid storage path');
   }