Use "LED intensity" in "Reference Image and Camera Settings" for internal AND external LED

[caco3]

Discussed in #3457

^{Originally posted by Ingo-Knito December 26, 2024}
If you are using external LEDs and want to change the brightness, it is quite complicated.
You set the R/G/B brightness in the settings, then do a reboot, wait and check the image in the reference image settings.
It would be much better to do this in the same way as for the internal LED settings

Actual

Settings > "LED Color": Set to R/G/B
Reboot
Wait....
Settings > References > Reference Image
Check if everything is fine
Otherwise: Start from the beginning

Idea: Eliminate the "LED Color R/G/B" in the settings and calculate a R/G/B-Value when using external LEDs.
99% == 255/255/255
50% == 128/128/128
10% == 26/26/26
The user only has to set the brightness (1..99) in the reference-image-settings.
The system knows whether the internal or external LEDs are being used - as set via the 'GPIO' settings.