So that is two layers of filler to create a perfect bed to print on?
But I think mesh bed can handle this.
Silver cubes with direct lighting https://github.com/lord-carlos/mk3-upgrade/blob/master/asset... Same cube with top down light: https://github.com/lord-carlos/mk3-upgrade/blob/master/asset...
What we have is Pressure Advanced. Where we stop extruding (as much) right before a corner. And we do that by doing some test prints with different values and eye balling it.
Also some firmwares like klipper have some math in it to compensate for heat expansion over time of the printers frame. Or something like that.