Add Stability AI section to models-featured.md

Author: ssalgadodev

articles/ai-foundry/concepts/models-featured.md

@@ -327,6 +327,7 @@ See the [Nixtla model collection in Azure AI Foundry portal](https://ai.azure.co
 | ------ | ---- | ------------ |
 | [tsuzumi-7b](https://ai.azure.com/explore/models/Tsuzumi-7b/version/1/registry/azureml-nttdata) | [chat-completion](../model-inference/how-to/use-chat-completions.md?context=/azure/ai-foundry/context/context) | - **Input:** text (8,192 tokens) <br /> - **Output:** text (8,192 tokens) <br />  - **Tool calling:** No <br /> - **Response formats:** Text |
 
+## Stability AI
 
 The Stability AI collection of image generation models include Stable Image Core, Stable Image Ultra and Stable Diffusion 3.5 Large. Stable Diffusion 3.5 Large allows for an image and text input.