Add PHP class auto-instrumentation to registry

[eerzho]

• I have read and followed the Contributing docs, especially the "First-time contributing?" section.
• This PR has content that I did not fully write myself.
  • I used AI and I have read and followed the Generative AI Contribution Policy.
• I have the experience and knowledge necessary to understand, review, and validate all content in this PR.¹

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Add eerzho/opentelemetry-auto-class to the registry.

This is a PHP instrumentation library that provides automatic OpenTelemetry tracing of class methods via the #[Traceable] attribute, with integrations for Laravel and Symfony.

Footnotes

1. Yes, I can answer maintainer questions about the content of this PR, without using AI. ↩

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: eerzho / name: eerzho (e750337)
• ✅ login: theletterf / name: Fabrizio Ferri-Benedetti (fe9b821)

[theletterf]

@open-telemetry/php-approvers Please have a look, thanks!