[feat] Image management functionality

[Kitenite]

Describe the feature

Continuation of https://github.com/onlook-dev/onlook/issues/1063 Currently, the UI is built and hidden on the LayersPanel side

1. The image tab should scan for the standard Next.js assets folder and find any images that can be used.
2. The images should be loaded into the sidepanel
3. Allow the ability to add image which will put it in the expected next.js standard folder
4. Add a search bar that just filters based on filename

Optional (can be separate PR)

1. Renaming the image should rename it but also find usage instance and refactor those as well
2. Support dragging the image into the frame which should add it to the target div's background, similar to the fill effect in the styles Panel