dsh-glm-vision: Integrating Zhipu GLM Vision Models into DeepSeek Harness

The DeepSeek Harness plugin `dsh-glm-vision` aims to address the lack of visual capabilities in local text models. By integrating Zhipu's GLM vision model, it provides image-viewing functionality for models such as DeepSeek. Users must install the plugin, configure a Zhipu API key, and restart DSH. It offers two usage modes—routing and tool-based—and supports local image paths and attachment IDs. By default, it takes over DeepSeek's official routing and automatically invokes GLM to analyze images when they are uploaded. Note that the plugin depends on `@deepseek-ai/schemastery` (>=3.18.0).