The ergonomic companion to `motionAttrs`: wrap any content to animate it IN and
OUT. `<Motion motion="scale-fade">…</Motion>` plays the preset's enter on mount
and its exit on removal (Svelte `out:` flips to `data-state='closed'` + retains
the node for the eidos-declared duration, like `<Cascade.Item>`). Rides the
existing state-presets — no new mechanism, no JS engine.
- morfo `motion.ts` (scope ['eidos']): one Provider part declaring `data-state`.
- eidos `motion/`: component (spreads `motionAttrs` + `out:` retention) + types +
index + README (incl. the `<Motion>` vs `motionAttrs` table + the content-domain
boundary).
- badge demo: a `<Motion>` show/hide example next to the prop showcase.
Caught + fixed a real collision: `data-motion` is already the reduced-motion prefs
attr (`[data-motion='reduce']`), so the wrapper emits NO part-presence marker (a
prefs `closest('[data-motion]')` would have matched it) — only the functional
`data-animation-style` + `data-state` from `motionAttrs`.
Verified at runtime: enter (data-state=open → `scale-in, fade-in`, no data-motion)
and exit (Hide → retained with data-state=closed → `scale-out, fade-out`). `check`
clean for the morfo + component + demo.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>