Interactive controls, velocity-card, and multi-framework support

The biggest quality-of-life improvement for the component browser arrived today: every major demo now has a live controls panel where you can adjust attributes in real time without touching code. Alongside that, the registry and docs received a round of structural work that sets a cleaner foundation for what comes next.

What changed

• Added velocity-card, a new interaction component that tilts and scales on pointer hover using velocity to drive transform intensity.
• Wired interactive attribute controls (sliders, toggles, selects, text inputs) to 14 component demos: card-stack, flip-card-stack, infinite-gallery, infinite-physics-gallery, magnetic, marquee, split-hover, split-reveal, stacking-words, text-loop, text-repel, text-scramble, video-player, and weight-wave.
• Added React, Svelte, and Vue integrations to the preview site and a new framework matrix test runner accessible at /docs/components/:slug/test.
• Introduced mk-text-input as a new control primitive, and extended mk-select to accept a JSON options attribute when no child elements are present.
• Moved all docs pages under the /docs/ prefix and added an Introduction page; the old /components/ and /changelog/ routes are gone.
• Migrated the root registry.json from a monolithic inline list to include-based per-group manifests under src/registry/<group>/registry.json.
• Fixed magnetic-element quickTo lifecycle so functions reinitialise on prop changes and clean up correctly on disconnect.
• Fixed a fullscreen preview bug where the card was reinserted before the placeholder was removed.

Why it matters

The interactive controls panel closes the loop between reading a component’s props and actually seeing them change. Being able to scrub a slider and watch the animation respond makes the catalog genuinely useful as a design tool, not just a showcase. The multi-framework test harness means component behavior can be verified in React, Svelte, and Vue without leaving the site.