agnes-media: DeepSeek Harness Media Generation Plugin

The `agnes-media` plugin for DeepSeek Harness (DSH) provides agents with text-to-image, text-to-video, and image-to-video capabilities. Released under the MIT license, it requires DSH 0.1.0-rc.7 and an Agnes AI Key to run. After installation, agents can invoke the `generate_image` and `generate_video` tools. Video generation is fixed at 720P, and the generation binding between the API key and endpoint should be noted. The plugin supports configuration via environment variables or DSH credentials, with asynchronous processing and automatic retry mechanisms.