migrate to vercel; bump version

src/lib/animations/engine.ts

@@ -0,0 +1,20 @@
+import { ANIMATION_IDS, DEFAULT_ANIMATION_ID } from "@/lib/animations";
+import type { AnimationId } from "@/lib/animations";
+
+export function getStoredAnimationId(): AnimationId {
+  if (typeof window === "undefined") return DEFAULT_ANIMATION_ID;
+  const stored = localStorage.getItem("animation");
+  if (stored && (ANIMATION_IDS as readonly string[]).includes(stored)) {
+    return stored as AnimationId;
+  }
+  return DEFAULT_ANIMATION_ID;
+}
+
+export function saveAnimation(id: AnimationId): void {
+  localStorage.setItem("animation", id);
+}
+
+export function getNextAnimation(currentId: AnimationId): AnimationId {
+  const idx = ANIMATION_IDS.indexOf(currentId);
+  return ANIMATION_IDS[(idx + 1) % ANIMATION_IDS.length];
+}