[Feature]: Add Azure Foundry Flux Image Generation Model Support

### The Feature

<img width="688" height="96" alt="Image" src="https://github.com/user-attachments/assets/980a5501-c473-4968-abe9-6d41d5bf753a" />

These models need to be added 

### Motivation, pitch

-

### LiteLLM is hiring a founding backend engineer, are you interested in joining us and shipping to all our users?

No

### Twitter / LinkedIn details

_No response_