Fixes#6552Fixes#6910Fixes#6872
Implementation of new node design. Includes many changes related to stylesheet update handling and per-style FRP construction, as well as refactoring of scene layers used by graph editor. Some additional components were migrated to use `Rectangle` shape and new mouse handling events. Fixed text rendering, where random thin lines appeared at the borders of glyph sprites. Refined edge layout to match new node sizes and not leave any visible gaps between line segments.
The node colors are currently randomly selected from predefined list. Later this will be improved to use group information from the suggestion database, once that is fully migrated to use the documentation tags, thus removing the dependency on the execution context.
https://github.com/enso-org/enso/assets/919491/aa687e53-a2fa-4e95-a15f-132c05e6337a
<img width="653" alt="image" src="https://github.com/enso-org/enso/assets/919491/30f3e897-62fc-40ea-b57b-124ac923bafd">
