Close the content domain of the universal `motion` prop (RFC §D.12/§D.13):
- State domain: a dedicated `data-motion-state` attribute lets a component with
its OWN data-state machine (Card selected/idle) drive a preset on its transition
without clobbering its semantic `data-state`. Enter-only (animate-on, snap-off).
New emphasis preset `select-pop` (no opacity-from-0, for still-visible elements).
- Loops (content domain, infinite): Tailwind's canonical `spin`/`pulse`/`ping`/
`bounce`, emitted as un-gated `[data-animation-style='X'] { animation: … infinite }`
rules. Themeable per loop via `--motion-loop-{name}`; reduced motion stops them.
- Staggered-exit bridge: the container-driven cascade now covers exit too —
`[data-stagger][data-state='closed'] > …` cascades children OUT in reverse
(`--motion-stagger-index-rev`, last leaves first). The container is retained for
the stagger window then unmounts (pragmatic CSS bridge for bounded lists; the
parent-waits-for-children version still needs the retired PresenceGroup).
- `[data-debug-stagger]`: opt-in dev affordance — a CSS counter badge per child
showing its `:nth-child - 1` index (the analog of UIX_DEBUG_MOTION).
- Fix `<Motion>` exit: a `{ duration }`-only Svelte transition never completes (the
node sticks at the exit frame, a re-show reuses the dead node); add a `tick` no-op
so it times the unmount.
Generated base.css regenerated; motion.test 27/27; docs (eidos-motion + RFC) updated.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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