Add Plausible analytics snippet

[luandro]

Summary

Add the Plausible tracking snippet so the docs site reports usage metrics now that https://docs.comapeo.app is configured in Plausible.

Details

We have already added the docs domain in Plausible. Follow the Docusaurus integration guidance from https://plausible.io/docs/docusaurus-integration and include the provided script tags at the top of each page.

<script defer data-domain="docs.comapeo.app" data-api="https://pls.comapeo.app/event" src="https://pls.comapeo.app/script.file-downloads.hash.outbound-links.tagged-events.js"></script>
<script>window.plausible = window.plausible || function() { (window.plausible.q = window.plausible.q || []).push(arguments) }</script>

Acceptance Criteria

• Plausible script loads globally across the docs site without breaking existing assets.
• Uses the custom domain and API endpoint configured above.
• Basic pageview events are verified in Plausible once deployed.