dsh-web-search-free: DSH Free Web Search Provider and MCP Server

`dsh-web-search-free` is an MIT-licensed DSH plugin designed to replace the pay-per-use official search service in DSH, providing anonymous, key-free web searches at no cost. This plugin is based on the Parallel or Exa free backends, requiring no balance consumption or API Keys. Its core features include: a toggle switch in DSH settings to alternate between official and free search, which automatically maintains the Profile patch file once enabled; and a built-in standalone MCP Server with zero dependencies, supporting stdio and HTTP/SSE transport methods, allowing the `web_search` tool to be integrated into other MCP clients such as Claude Code and Codex. During installation, the plugin must be added via the official DSH command, and within the