[feat] Ability to query/set multiple display brightness

[Nixes]

Description (What is the problem)

On a system with multiple displays (macOS / Windows) it would be beneficial to be able to set different brightness settings for each display. Especially in the case that the displays have different brightness capabilities.

Solution suggestion

Allow querying of list of display devices. Allow reading or setting brightness for each display.

[aaassseee]

Hi @Nixes. This will be implement after linux support is completed.