Add image generation tools

[yxjiang]

Summary

Add the image generation tools, oai image gen and replicate image gen with wan 2.2.

Test Plan

    "Create a whimsical scene inside a modern subway train featuring a "
    "fluffy, light brown rabbit and a chubby, soft gray penguin sitting "
    "side by side on blue plastic seats. The background includes tall "
    "city buildings visible through a large window and a colorful framed "
    "picture on the wall. Soft, natural lighting filtering through the "
    "window enhances the cheerful atmosphere. The image should be "
    "hyper-realistic with fine textures on the animals' fur and "
    "feathers, emphasizing their cuteness while maintaining a playful "
    "and friendly mood."