Add atom-theme visual design (header/footer, theme system, restyled pages)

Faithful port of AtomCMS's "atom" theme look (light, Habbo-retro, golden
#eeb425 / amber #f59e0b accents, white cards, 12px radii, Nunito-first stack):
- globals.css: full token set + components (.site-header/.nav-item, .btn-*,
  .card, .hero, currency pills, article cards, inputs, tables, footer).
- SiteHeader (brand + nav + currency pills + auth box, staff-aware) + SiteFooter;
  layout wraps header/content/footer. Removed the bare SiteNav.
- Restyled home (hero + article cards), login (centered card).
- siteSettings now falls back to DEFAULTS on missing key OR DB error, so pages
  render without a DB; DATABASE_CONNECT_TIMEOUT_MS env + pool acquireTimeout make
  the no-DB fallback fast.

Verified in a real browser (computed styles): header white/sticky, golden logo
gradient, uppercase nav, amber primary button @12px radius, golden outline,
hero gradient — all correct. tsc exit 0, vitest 48/48, next build exit 0.

src/lib/prisma.ts

@@ -13,7 +13,8 @@ function createPrismaClient(): PrismaClient {
     password: decodeURIComponent(url.password),
     database: url.pathname.replace(/^\//, ""),
     connectionLimit: env.DATABASE_POOL_SIZE,
-    connectTimeout: 10_000,
+    connectTimeout: env.DATABASE_CONNECT_TIMEOUT_MS,
+    acquireTimeout: env.DATABASE_CONNECT_TIMEOUT_MS,
     idleTimeout: env.DATABASE_IDLE_TIMEOUT_MS,
   });
   return new PrismaClient({