perf: add bans.user_id index, Redis cache layer, rate-limit improvements, radio contest/giveaway columns, and tests

- Add DB index on bans.user_id to speed up per-request ban lookups (migration 0008)
- Replace in-process rate limiter with Redis-backed implementation with in-memory fallback
- Add Redis caching layer for site settings with TTL invalidation (migration 0009)
- Add rate limiting to resetPassword to prevent token brute-force attacks
- Update all rateLimit callers to await the now-async function
- Flesh out RadioContests and RadioGiveaways models with title, description, prize, date, and winner columns
- Update radio contest/giveaway pages to display new fields
- Add tests for rate limiter (4 tests) and password-reset actions (3 tests)
- Add REDIS_URL environment variable (optional, falls back to in-memory)

src/app/radio/contests/page.tsx

@@ -12,11 +12,12 @@ function formatDate(d: Date | null | undefined): string {
 export default async function RadioContestsPage() {
   const t = await getTranslations("pages.radioContests");
 
-  // RadioContests.id is a BigInt — stringify before use in keys/routes.
   const contests = await prisma.radioContests
     .findMany({
-      orderBy: { createdAt: "desc" },
+      where: { isActive: true },
+      orderBy: { startDate: "desc" },
       take: 50,
+      select: { id: true, title: true, prize: true, startDate: true, endDate: true },
     })
     .catch(() => []);
 
@@ -43,10 +44,15 @@ export default async function RadioContestsPage() {
                   style={{ color: "inherit", textDecoration: "none", display: "grid", gap: "0.3rem" }}
                 >
                   <h3 style={{ margin: 0, fontSize: "1rem" }}>
-                    <span aria-hidden>🎉</span> {t("contestLabel", { id })}
+                    <span aria-hidden>🎉</span> {c.title || t("contestLabel", { id })}
                   </h3>
-                  <p className="muted" style={{ margin: 0 }}>
-                    {formatDate(c.createdAt) || t("dateUnknown")}
+                  {c.prize ? (
+                    <p className="muted" style={{ margin: 0, fontSize: "0.9rem" }}>
+                      Prize: {c.prize}
+                    </p>
+                  ) : null}
+                  <p className="muted" style={{ margin: 0, fontSize: "0.85rem" }}>
+                    {c.startDate ? `${formatDate(c.startDate)} — ${c.endDate ? formatDate(c.endDate) : "ongoing"}` : t("dateUnknown")}
                   </p>
                 </Link>
               );