Insufficient image quality due to downsampling

[xsm1997]

Describe the bug and how to reproduce
The images get downsampled even full resolution is selected in preferences.

It will be fine when just looking at it. But when I zoom the image, the image quality will be bad, far behind the original image.

Steps to reproduce the behavior:

1. Open any photo

Expected behavior
Original image should be displayed if full resolution is set.

Smartphone (please complete the following information):

• Device: iPad Pro 11 (4th gen, M2)
• OS: iOS 17.1
• App version 3.0.2

Additional context

Piwigo-Mobile/piwigo/Image/ImagePreviewViewController.swift

Line 93 in 47f0dc5

let cachedImage = ImageUtilities.downsample(imageAt: cachedImageURL, to: cellSize, scale: scale)

Maybe we shouldn't downsample the image here? There is no such issue before 3.0.0 version.