When a user explicitly configures a model for the multimodal-looker
agent (e.g. zhipuai-coding-plan/glm-5.1), treat that model as
vision-capable even when its provider config does not declare
modalities.input or capabilities.input.image. This unblocks
vision-capable models that the provider config does not advertise.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>