Backlight/Brightness using ddcutil

Hello

While backlight slider module works on laptop, I wonder if on desktops we can use ddcutil module to change external module brightness.

Thanks

Start by locating the existing backlight slider module and reviewing how it changes laptop brightness. Then investigate whether ddcutil can provide a compatible path for external monitors on desktop Linux. Done would require a defined integration scope and verified brightness control behavior, but the issue does not name files or tests.

Written by the indexing model from the issue text.