llm-deepseek-image-admit: DeepSeek Image Admission

DeepSeek's official model metadata restricts image admission. This plugin takes over the official routing and modifies the metadata—completing `inputModalities` to `['text', 'image']`—to bypass the harness's image blocking and allow image messages to pass admission pre-checks. It relies on the official artifact layout, transmits no images via the API, and must be used with plugins such as `image-bridge` to transcribe image content during the `pre-step` stage, without changing user behavior. The installation command is `dsh plugin --profile web add github:Seryta/llm-deepseek-image-admit`.