problematic demos

Excluding "minor" coloring/lightning/tonmapping issues https://github.com/pmndrs/examples/issues/11

Here are the "problematic" demos that:

does not build

Some demos/* have been temporarily disabled (renamed "bbuild2" with 2 "b" instead of "build2" like others one) because of build errors.

For them, please test with:

$ npm run -w demos/bvh bbuild2
$ # if succeeded, renane `demos/bvh/package.json#scripts.bbuild2` into `build2`

• https://pmndrs.github.io/examples/demos/bvh
• https://pmndrs.github.io/examples/demos/grass-shader
• https://pmndrs.github.io/examples/demos/infinite-scroll
• https://pmndrs.github.io/examples/demos/interactive-spline-scene-live-html
• https://pmndrs.github.io/examples/demos/racing-game
• https://pmndrs.github.io/examples/demos/space-game
• https://pmndrs.github.io/examples/demos/spline-glass-shapes
• https://pmndrs.github.io/examples/demos/threejs-journey-portal

is blank or error(s) in console

$ npm run -w demos/basic-ballpit dev

• https://pmndrs.github.io/examples/demos/basic-ballpit
• https://pmndrs.github.io/examples/demos/flexbox-yoga-in-webgl
• https://pmndrs.github.io/examples/demos/gpgpu-curl-noise-dof
• https://pmndrs.github.io/examples/demos/horizontal-tiles
• https://pmndrs.github.io/examples/demos/html-input-fields
• https://pmndrs.github.io/examples/demos/inter-epoxy-resin
• https://pmndrs.github.io/examples/demos/monitors
• https://pmndrs.github.io/examples/demos/mount-transitions
• https://pmndrs.github.io/examples/demos/nextjs-prism
• https://pmndrs.github.io/examples/demos/shader-fire
• https://pmndrs.github.io/examples/demos/shadermaterials
• https://pmndrs.github.io/examples/demos/simple-physics-demo-with-debug-bounds
• https://pmndrs.github.io/examples/demos/sparks-and-effects
• https://pmndrs.github.io/examples/demos/springy-boxes
• https://pmndrs.github.io/examples/demos/svg-maps-with-html-annotations
• https://pmndrs.github.io/examples/demos/the-three-graces
• https://pmndrs.github.io/examples/demos/zustand-site

something is broken compared to original

• https://pmndrs.github.io/examples/demos/inverted-stencil-buffer -- no portal
• https://pmndrs.github.io/examples/demos/router-transitions -- routing is not working
• https://pmndrs.github.io/examples/demos/stage-presets-gltfjsx -- no car model
• https://pmndrs.github.io/examples/demos/stencil-mask -- no portal

Start with the unchecked demos listed in the issue, using the provided npm commands: run the relevant bbuild2 script for build failures and npm run -w demos/ dev for blank or console-error cases. Compare the affected demos with their original behavior where noted. Done means each targeted demo builds, runs without the reported errors, or matches the stated original behavior.