Improve viewport readability and configurable scene renderingPr/lighting readability

[aaron4ce]

Draft PR for:
CommonWealthRobotics/CaDoodle-Application#313

This updates BowlerStudio viewport rendering to improve readability while keeping the scene behavior configurable.

Changes include:

• configurable stable viewport lighting
• preservation of the original BowlerStudio lighting through lighting.mode=kevin
• configurable grid brightness, opacity and line width
• configurable grid behavior while the camera is moving
• scene style configuration through SceneStyleConfig
• update to the bowler-script-kernel feature-edge/thumbnail branch
• cleanup of the viewport rendering code after the initial experiments

The current default scene uses the stable lighting setup, but the original BowlerStudio-style lighting and grid behavior remain available through configuration.

While rebasing this work onto the current development branch, the recent camera/hand/grid changes from upstream were preserved. In particular, the newer hand rendering and grid alignment behavior remain in place.

Validation:

• full CaDoodle build passes with the updated BowlerStudio and kernel
• tested with large STL meshes around 20 MB
• tested with two large meshes loaded at once
• also tested with -XX:ActiveProcessorCount=2
• viewport interaction remained responsive during these tests
• feature edges and lighting were visually checked after the rebase

This is still a Draft PR. Feedback on rendering flow, configuration, and where heavier geometry processing should live would be very useful before further refactoring.

[madhephaestus]

I'd prefer not to rename variables in a PR that is also adding features.

[madhephaestus]

will this need an update to all of the stylesheets in StyleCadoodle?