[agents-md] Index bundled docs instead of downloading into .next-docs (#94719)
Since 16.2.0 the published `next` package ships its docs at `dist/docs`
(#89850), but `codemod agents-md` still git-clones a copy into
`.next-docs`. When the install resolved from `cwd` has bundled docs and
its version matches the requested one, the generated index now points at
`./node_modules/next/dist/docs` directly — no clone, no `.next-docs`, no
`.gitignore` entry. Older versions and explicit `--version` mismatches
keep the download path.
Covered by new e2e tests: bundled-docs indexing, `--version` match, and
download fallback on mismatch.
<!-- NEXT_JS_LLM_PR -->
next.js
aaea98af - [agents-md] Index bundled docs instead of downloading into .next-docs (#94719)
