Control saturation range

[leoyala]

🚀 Feature Request

It would be ideal to have a way to control the lower and upper boundaries that control the saturation limits for the display. This could be done, for example, through a slider that is displayed on hover when the saturation tool button is activated.

🔈 Motivation

Currently, the saturation range (50, 950) is hard-coded and cannot be changed by the user.

🛰 Alternatives

Allow writing the values in the JSON configuration file for xilens.