add web analytics to https://rust.iceberg.apache.org/

### Is your feature request related to a problem or challenge?

Similar to https://github.com/apache/iceberg/issues/14157

add Matomo to https://rust.iceberg.apache.org/

### Describe the solution you'd like

_No response_

### Willingness to contribute

None

Start by reviewing the related Apache Iceberg issue 14157 and the repository entry points for the rust.iceberg.apache.org site. Determine where site-wide analytics configuration belongs and confirm the expected Matomo setup. Done means Matomo tracking is present on the site without disrupting its existing build or deployment.

Written by the indexing model from the issue text.