dsh-tui-mcp-manager: dsh-TUI's Native MCP Server Management Plugin

dsh-tui-mcp-manager is a native plugin that provides a full-screen MCP management interface for dsh-TUI. Users can manage the server pool, Sets orchestration, tool browsing, and credential references via the `/mcp-manager` command. The plugin supports creating, editing, and starting/stopping servers, as well as running diagnostic checks. Configuration files are written atomically to ensure safety, and sensitive values are retained only as references. Installation requires Node.js ^22.19 or >=24, dsh 0.2.0-rc.1, and dsh-TUI >=0.11.2.