refactor(all): migrate from React to Next.js

src/lib/site.ts

@@ -0,0 +1,17 @@
+const trimTrailingSlash = (value: string) => value.replace(/\/$/, "");
+
+export const siteUrl = trimTrailingSlash(
+  process.env.NEXT_PUBLIC_SITE_URL || "http://localhost:8080",
+);
+
+export const apiBaseUrl = trimTrailingSlash(
+  process.env.NEXT_PUBLIC_API_BASE_URL || "http://127.0.0.1:8000",
+);
+
+export const toAbsoluteUrl = (value?: string | null, fallbackBase = siteUrl) => {
+  if (!value) return undefined;
+  if (/^https?:\/\//i.test(value)) return value;
+  const normalizedBase = trimTrailingSlash(fallbackBase);
+  const normalizedPath = value.startsWith("/") ? value : `/${value}`;
+  return `${normalizedBase}${normalizedPath}`;
+};