feat: add optional background color for big gcode thumbnails

[meteyou]

Description

This PR adds a optional background color to gcode thumbnails.

Related Tickets & Documents

fixes: #1507

Mobile & Desktop Screenshots/Recordings

Start print dialog:

Status panel:

Gcode list:

Settings:

[optional] Are there any post-deployment tasks we need to perform?

none

[github-actions]

Language file analysis report:

File	Missing Keys	Unused Keys
en.json	0	4

[github-actions]

Language file analysis report:

File	Missing Keys	Unused Keys
en.json	0	4

[github-actions]

Language file analysis report:

File	Missing Keys	Unused Keys
en.json	0	4

[EmJay276]

Is it possible to add an "autodetection" of the background color based on the image color?
Dark picture => light background
Bright picture => dark background

[meteyou]

@EmJay276 i don't think so and/or i don't see a benefit to add a huge lib to detect the image for such a small use-case...

[EmJay276]

@meteyou
This here seems to work without a big library
https://stackoverflow.com/questions/38211798/detect-if-image-is-dark-light-and-addclass-dark-light-to-parent

[meteyou]

@EmJay276 hmm... that could work, but is a a bigger rework. can you please open a new FR with this link? so i can add this for the next release. for this release, i would just merge this PR and extend it with the next one.

[github-actions]

Language file analysis report:

File	Missing Keys	Unused Keys
en.json	0	4