fix: Remove hardcoded example from Scan Ebooks Bruno request

- Remove hardcoded folder_paths example from request body
- Allow flexible folder path configuration per request
- Improve request flexibility for different scan scenarios

bruno/scanner/Scan Ebooks.bru

@@ -9,11 +9,3 @@ post {
   body: json
   auth: bearer
 }
-
-body:json {
-  {
-    "folder_paths": [
-      "/path/to/test/ebook/folder"
-    ]
-  }
-}