Get Figma Guidance to MCU starting guide

https://wiki.qt.io/Getting_Started_with_Qt_Bridge_for_Figma

Especially in the context of MCU we have to emphasize that the Figma file has a good strucutre, free of unesseary items and complexity. Variants should not be used to defines differen screens.
Merging/backing assets to images takes memory.

Scaling and opacity is most likely expensive.

Proposal:

"When designing in Figma for exporting directly to QML for Qt4Mcu, you have to keep the structure minimal and avoid unnecessary items because they come with a cost of memory and performance. Do not use variants to define screens that look really different. Use components instead and only change the visibility if you want to use variants.
Remember that merging layers will raster items into images during export, and memory consumption can be huge.
Using opacity and scaling usually has a severe performance impact on MCU systems."