feat: 1-to-1 message render + web data-lake backend

frontend/src/lib/transitions/appear.ts

@@ -0,0 +1,19 @@
+import { cubicOut } from "svelte/easing";
+
+interface AppearParams {
+  disabled?: boolean;
+}
+
+export function appear(
+  _node: HTMLElement,
+  { disabled = false }: AppearParams = {}
+) {
+  if (disabled) {
+    return { duration: 0 };
+  }
+  return {
+    duration: 200,
+    easing: cubicOut,
+    css: (t: number) => `opacity: ${t}; transform: scale(${0.85 + t * 0.15});`,
+  };
+}