Compare Variant improvement

Add the ability to resize the window and fix the scale, as well as fix the photo, regardless of its location, the ability to select photos from a selection of Variants.

1. Sometimes a narrow window is needed for a Variant to fit a face or a piece of clothing, in this case the Variant will not take up much useful space on the screen.

2. It should be possible to fix the scale and position of the Variant so that it does not depend on changes in other photos, the Variant should be static (especially when we change the scale and position with the Shift key pressed).

3. Now the Variant is relevant only for the current active folder. This is a problem if you need to apply the same Variant to different folders.

4. Add the option to specify a folder with Variants . For example, if you click on a sample, the viewer at the bottom will display all the samples from the specified folder or all the selected samples, respectively, it should be possible to select several Variants for storage and then switch between them. If you click on the photo on the right (the photo is not a Variant), then the files from the currently active folder are displayed in the viewer again.