[Proposal] Gemma4 Architecture Adapter

[jlarson4]

Proposal

Create an architecture adapter for Gemma 4

Motivation

This is a community request, and the next obvious step in our support of the Gemma family of models

Pitch

Use the transformers reference and our Architecture Adapter Creation Guide to add support for the Gemma 4 family of models

Checklist

• I have checked that there is no similar issue in the repo (required)

[huseyincavusbi]

Ready to work on these! @jlarson4