dsh-qqbot-dafeiyu: QQ Bot IM Channel Plugin

dsh-qqbot-dafeiyu is a QQ plugin for DeepSeek Harness that uses QQ messages as the front-end protocol for agents. It supports private/group chat session isolation, Markdown output, image generation, and TTS. During installation, configure an AppID/Secret or log in by scanning a QR code. Developers should note that the whitelist policy is enabled by default, and that `open` mode exposes host capabilities, so it should be exposed externally with caution.