Add Better Auth admin authentication

lib/route-guards.ts

@@ -1,5 +1,14 @@
-import type { MockSession } from "@/lib/mock-auth";
-
-export function getDashboardRedirectPath(session: MockSession | null) {
-  return session ? null : "/";
+export function isDashboardPath(pathname: string) {
+  return pathname.startsWith("/dashboard");
+}
+
+export function shouldRedirectDashboardRequest(
+  pathname: string,
+  hasSession: boolean,
+) {
+  return isDashboardPath(pathname) && !hasSession;
+}
+
+export function getDashboardRedirectPath(hasSession: boolean) {
+  return hasSession ? null : "/login";
 }