feat(dependencies): add Lottie animation libraries and refactor NotFoundPage

- Added `@lottiefiles/dotlottie-react` and `lottie-react` dependencies for enhanced animation capabilities.
- Refactored the NotFoundPage component to utilize a dedicated NotFoundContent component, improving code organization and readability.
- Updated package.json and pnpm-lock.yaml to reflect new dependencies and their versions.

src/lib/lottie-theme.ts

@@ -0,0 +1,66 @@
+/**
+ * Brand-aligned Lottie tinting (Tailwind theme tokens → normalized RGBA).
+ * Primary: #5750F1 — slightly lifted in dark mode for contrast on `dark` bg.
+ */
+
+export type LottieThemeMode = "light" | "dark";
+
+/** #5750F1 */
+const PRIMARY_LIGHT = [87 / 255, 80 / 255, 241 / 255, 1] as const;
+/** Brighter violet for fills on #111928 */
+const PRIMARY_ON_DARK = [125 / 255, 118 / 255, 252 / 255, 1] as const;
+
+function deepClone<T>(value: T): T {
+  return JSON.parse(JSON.stringify(value)) as T;
+}
+
+function colorsMatch(a: unknown, b: readonly number[]): boolean {
+  if (!Array.isArray(a) || a.length !== 4) return false;
+  return a.every(
+    (v, i) => typeof v === "number" && Math.abs(v - b[i]!) < 0.0001,
+  );
+}
+
+/**
+ * Replace exact RGBA quadruples anywhere in the JSON tree (Lottie uses nested `c.k`).
+ */
+function replaceRgbaEverywhere(
+  node: unknown,
+  from: readonly number[],
+  to: readonly number[],
+): unknown {
+  if (node === null || typeof node !== "object") {
+    return node;
+  }
+  if (Array.isArray(node)) {
+    if (colorsMatch(node, from)) {
+      return [...to];
+    }
+    return node.map((item) => replaceRgbaEverywhere(item, from, to));
+  }
+  const out: Record<string, unknown> = {};
+  for (const [k, v] of Object.entries(node)) {
+    out[k] = replaceRgbaEverywhere(v, from, to);
+  }
+  return out;
+}
+
+/** Pure black fills/strokes → brand primary (loading spinner dots, etc.). */
+export function applyLoadingLottieTheme<T extends object>(
+  data: T,
+  mode: LottieThemeMode,
+): T {
+  const clone = deepClone(data);
+  const to = mode === "dark" ? PRIMARY_ON_DARK : PRIMARY_LIGHT;
+  return replaceRgbaEverywhere(clone, [0, 0, 0, 1], to) as T;
+}
+
+/**
+ * Full illustrations (e.g. 404): clone only until we add palette maps per asset.
+ */
+export function applyIllustrationLottieTheme<T extends object>(
+  data: T,
+  _mode: LottieThemeMode,
+): T {
+  return deepClone(data);
+}