DeepSeek Harness Plugin: dsh-models-input-modalities

The `dsh-models-input-modalities` plugin addresses configuration pain points by exposing previously hidden model capability fields in the DeepSeek Harness Web interface. It allows users to directly select input modalities (text/images) and reasoning levels without manually editing YAML. It supports localization, conflict handling, and configuration migration, providing users with more intuitive configuration control.