dsh-mcp-oauth-client: General-purpose MCP Management and Client Bridge Plugin

`dsh-mcp-oauth-client` is a universal MCP management plugin for DeepSeek Harness (DSH). It addresses the complexity and error-proneness of native YAML configuration by providing a visual management interface. The plugin supports both HTTP (including streaming authentication methods such as OAuth 2.1 and Bearer tokens) and stdio (local process) service types, and offers capabilities for creating, reading, updating, and deleting services, as well as automated OAuth authorization and token refresh. It is installed via npm, and its configuration is written to a profile file. Users should be aware of security and compatibility considerations, such as plaintext credential storage and token persistence in memory.