dsh-web-fetch-moli: Lightweight Moli Backend

`dsh-web-fetch-moli` is a lightweight plugin for DeepSeek Harness (DSH) designed to address the high resource consumption of traditional browsers when rendering SPAs and micro-frontends. Built on the Rust-based Moli backend, it keeps memory usage around 50–60 MB, reducing consumption by over 90% compared with standard browsers. The plugin supports both local and CDP backend modes, handles Cloudflare challenges, removes content noise, and generates GitHub-Flavored Markdown, making it suitable for resource-constrained scenarios requiring high-concurrency scraping of dynamic pages.