docs: add VitePress documentation site with GitHub Pages deployment (#127)

* docs: deduplicate documentation — single source of truth in docs/

- Remove root CDP.md, CDP.zh-CN.md, CLI-ELECTRON.md (now in docs/advanced/)
- Slim adapter READMEs to one-liner + link to docs/ (11 files)
- Update README.md adapter table links to point to docs/

* docs: set VitePress base path for GitHub Pages deployment

docs/.vitepress/config.mts

@@ -1,6 +1,7 @@
 import { defineConfig } from 'vitepress'
 
 export default defineConfig({
+  base: '/opencli/',
   title: 'OpenCLI',
   description: 'Make any website or Electron App your CLI — AI-powered, account-safe, self-healing.',