suggestion: Flash overlays instead of bundling

[azan-n]

The Redmi Note 10 and 10S have essentially the same display which means the SystemUI overlays should fit nicely with each other. I was thinking that instead of bundling in all overlays, we could just create releases with build-scripts so that the user only flashes their own. This will help in the following ways:

1. Reduce the clutter in the /product part.
2. Allow the project to scale without having redundant files and exorbitant file sizes.
3. Assure the user that they have been using the correct overlay.

The current build system is efficient but it seems it will not scale very well as devices increase. Furthermore, I think we could also find a way for the user to access which overlays have been activated.

I'll be glad to help out if it is required.

#535 might help since it is essentially the same device.
Originally posted by @azan-n in #605 (comment)

Overlays need to exist for individual devices separately as no two devices come with same power profiles & brightness stack at the least.
It's possible to automate some booleans. But that's about it.

[phhusson]

How will user flash it?