When max_images could not be detected (e.g. Kilo gateway doesn't
support OpenAI image format, probe returned 0), chunking was
disabled entirely and all screenshots sent in a single request.
Nvidia NeMo still enforces an 8-image limit regardless of the
gateway, causing 400 errors.
Fix: default to 8 images per chunk when max_images is 0 or None,
so chunking always applies for multi-tab dashboards.