[bug]: Black images don't work for Inpaint Mask, Images less than 600px can't be used for Flux.2 Ref image

### Is there an existing issue for this problem?

- [x] I have searched the existing issues

### Install method

Invoke's Launcher

### Operating system

Windows

### GPU vendor

Nvidia (CUDA)

### GPU model

RTX5070ti

### GPU VRAM

16GB

### Version number

6.14.0

### Browser

_No response_

### System Information

_No response_

### What happened

I was trying to transfer styles from an image to Icons, First issue I noticed is that black images can not be used as control layers, The Models totally ignore black images.
So for instance i wanted to use a control layer to generate the structure of an Icon on the default transparent background (No Raster Layer). I added a totally black icon outline, Clicked "Invoke", it just made a random image and didnt follow the composition.
To test, I opened up the image in Photoshop and inverted the colours, dropped the White icon outline into the control layer and clicked "Invoke" it then followed the compostion exactly.

Another problem I detected was that images smaller than 600px will not work as reference images for Flux.2

Maybe not a problem with Invoke, they might be a Model specific issue for Flux.2 or a Control Adapter issue, but seemed to be the same with both SDXL and Flux 1 Control Adapters.

Just thought i would mention it incase someone else thinks they are going mad aswell 😆

### What you expected to happen

Totally black images to be used correctly by the Control Adapter.
Flux2 to be able to use references smaller than 600px, such as 512pxx512px icons.

### How to reproduce the problem

_No response_

### Additional context

_No response_

### Discord username

_No response_