dsh-wsl-im: Integrating Instant Messaging Platforms into DeepSeek Harness

`dsh-wsl-im` is a plugin for DeepSeek Harness that bridges Web profiles and instant messaging (IM) platforms. It supports multiple platforms such as Feishu and Slack, and triggers replies by injecting message streams into `ctx.agents`. After installation, environment variables must be configured to enable the adapters, and Node.js dependencies are used to handle platform-specific logic. The plugin supports mock testing and allows whitelists to be configured to enhance security, while also providing platform-specific connection and usage notes (for example, WeCom requires a proxy, and Discord requires enabling intents).