dsh-im-hub: Adding Lark, WeCom, and Telegram Message Gateways for DeepSeek Harness

dsh-im-hub is a multi-platform IM gateway plugin for DeepSeek Harness (v0.2.3, MIT License) designed to seamlessly integrate DSH agents into Lark, WeCom, and Telegram without the need for redundant frontend development. Its core capabilities include support for platform-specific connection methods: Lark supports WebSocket long connections and Webhooks, WeCom employs a callback mode with AES-256-CBC decryption and signature verification, and Telegram utilizes long polling with message splitting based on character limits. Additionally, it provides a Mock adapter for local testing. In terms of session management, the plugin supports independent sessions isolated by chat, preserving multi-turn context and processing dialogue turns serially, while idle sessions are automatically recycled. In terms of access control, it supports access control via allowe...