Image Reference Tab Request In Manual Mode.

## Is your feature request related to a problem? Please describe.
NO, it is not! Its not a problem but its a need for this project!

## Describe the solution you'd like

When I checked the Manual override in the Img Gen section I thought of using my own consistent character Image generating model But when I used my model in the latest 3.1.0 Alpha version I could'nt see any reference Image tab so I thought of exploring a little bit.
I saw Intel playground Videos and saw that the latest version of Playground Does not acutally support the reference image in the Manual mode!
Well I think it will be a really good feature If you add it actually!
But I will Admit! I have been with AI playground from around 1-1.5 years!
its getting better in my opinion or in my honest review!
## Describe alternatives you've considered
You can add this in either the Img edit or the Img Gen tab

## Additional context
None actually!
Thank you!

Start in the Img Gen Manual override flow and compare it with the Img edit flow, focusing on how the 3.1.0 Alpha handles model inputs. Define the reference-image behavior for manual mode and verify it works with a custom consistent-character model.

Written by the indexing model from the issue text.