refactoring, bugfix on surface optimisation (still some work needs to be done, but probably not too relevant), addition of some new surface gen features

add bugfixes from slicer-mini/28487d467c5186c82c282b48079b2620440d05e3, 7524ea52d560a24365f8b449e8faa66dcee1f7d1, 6a6856d83aa146d3b99af5e30b5db9c5a2bf088e

add bugfixes from slicer-mini/71065a40a2baebcb031611930f614263017d3842 and slicer-mini/bf5621bb6b5ff1ef1e347058a19e1bef67267523

split transforms into translations and quaternion rotations. this way if a point is subject to multiple transforms, an average transform can be obtained

separate addition of stress vectors to mesh into own function. add option to normalise vector direction

found bug where model mesh was being transformed to print bed centre, but stress data was not shifted with it. need to fix

update cost function for given indices inplace (no longer copies slice from dataframe and reassigns)

stress aligned layers now start warping from previous layer. Cost function is evaluated from surface normals. Stress field needs smoothing big time