A scene is now a GLTS asset that builds into glts's `scene` instead of a module that exports
one. The CLI loads it with @drawcall/glts, resolving the scene's packages as its own first so the
scene shares three, physics and robotics, and calls its frame callbacks before each step. Viewer
topics and the recording filter move from module exports to `getROS2().show` and
`.recordExclude`.

Scenes stay plain browser-style Three.js: the CLI supplies what a page would, `fetch` for file:
URLs, `ProgressEvent` and `createImageBitmap` (decoded with sharp), and uploads decoded images
through Dawn's writeTexture, since Dawn takes no external image sources. so101 now loads its
textures, environment map, chess set and arm meshes with Three.js's own loaders.

The bin is `robotics`, so `npx @drawcall/robotics` runs it. The robot-task skill moves to the
so101-real experiment; the package ships only the robotics authoring skill.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>