docs: link Qwen3-235B and Wan2.2-14B recipes in README

[akrishnakanth]

Description:

Updated the root README.md model matrix to include links for existing G4 (Blackwell) recipes:

- Qwen3-235B (TensorRT-LLM)

- Wan2.2-14B (SGLang)

This ensures these recipes are discoverable from the repository's main landing page.

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[Chris113113]

@akrishnakanth please follow the CLA onboarding instructions at https://github.com/AI-Hypercomputer/gpu-recipes/pull/200/checks?check_run_id=72281425318