Explorer connect instructions use broken latest release URL

## Summary

The SDK explorer connection instructions still use the old `releases/download/latest` URL for the Linux Ceramic One tarball:

```bash
https://github.com/ceramicnetwork/rust-ceramic/releases/download/latest/ceramic-one_x86_64-unknown-linux-gnu.tar.gz
```

That path downloads the GitHub error response instead of the release asset because `latest` is not a real tag in that URL format. This is the same URL pattern described in #400.

## Expected

Use GitHub's latest-release redirect URL:

```bash
https://github.com/ceramicnetwork/rust-ceramic/releases/latest/download/ceramic-one_x86_64-unknown-linux-gnu.tar.gz
```

## Impact

Users following the explorer's connect instructions can download an invalid archive and then hit `tar: Error opening archive: Unrecognized archive format`.

Search the explorer connection instructions for the rust-ceramic Linux tarball URL shown in the issue. Replace the old releases/download/latest pattern with the releases/latest/download form, then verify the documented asset path matches the expected URL and no duplicate outdated pattern remains.

Written by the indexing model from the issue text.