fix(deps): next-auth beta.30 -> beta.32 — the advisory targets next-auth itself

The #22 bump patched @auth/core to 0.41.3 but trivy also flags the
next-auth package directly (CVE-2026-73420 CRITICAL + CVE-2026-73421,
existence-based auth bypass on configuration errors), both fixed in
5.0.0-beta.32. Tests 80/80 at 100% coverage; typecheck, lint, build
clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

package.json

@@ -24,7 +24,7 @@
     "geist": "^1.7.2",
     "lucide-react": "^1.17.0",
     "next": "16.2.11",
-    "next-auth": "5.0.0-beta.30",
+    "next-auth": "5.0.0-beta.32",
     "react": "19.0.0",
     "react-dom": "19.0.0",
     "tailwind-merge": "^3.6.0"