A `/demos/motion` page showcasing the content domain:
- Loops (spin/pulse/ping/bounce) on clean SVG via `motionAttrs`.
- Enter → loop → exit lifecycle on a pigeon SVG adapted from the `/demos` paloma
(the page has no ActiveEidos provider, so it loads the static eidos CSS and
replicates `<Motion>`'s exit inline).
- Staggered list: container-driven cascade IN (first item first) and OUT in reverse
(last leaves first), retained then unmounted — the §D.13.2 bridge.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
