Port AtomCMS atom theme faithfully (Tailwind v4 + real CSS/assets + shell)

Make the template match the atom theme, not just approximate it:
- Add Tailwind v4 (+forms/typography plugins, postcss) and port the real atom
  CSS (global.css + atom app.css) into globals.css: nav-item underline, currency
  + navigation icon classes, site-bg, card-base/hover-lift, text utils — asset
  paths adapted to /assets.
- Copy the real theme assets (backgrounds, icons/currency/navigation, profile,
  leaderboards) into public/assets.
- Rebuild the shell 1:1 from the atom Blade: TopHeader (currency pills +
  user/admin dropdowns, auth-only), SiteHeader (header image + black/50 overlay,
  logo+online+Nitro client / guest Login+Create-account CTA), Navigation (white
  bar, nav-item + Community/Assistance dropdowns), Footer. ThemeVars injects the
  DB-driven CSS custom properties into :root like app.blade.php. Layout uses the
  atom body/site-bg + grid-cols-12 max-w-7xl content wrapper.

Verified: tsc 0, next build exit 0; curl confirms the atom markup, compiled CSS
references the assets, and background-light.jpg + currency/navigation icons all
serve 200.

src/components/theme-vars.tsx

@@ -0,0 +1,58 @@
+import { siteSettings } from "@/lib/services/site-settings";
+
+// Injects the DB-driven CSS custom properties into :root, exactly like
+// AtomCMS's app.blade.php. Falls back to the atom defaults when no DB.
+export async function ThemeVars() {
+  const g = (k: string, d: string) => siteSettings.get(k, d);
+  const [
+    primary,
+    background,
+    surface,
+    dropdown,
+    navbar,
+    navbarText,
+    text,
+    textMuted,
+    accent,
+    buttonColor,
+    buttonText,
+    borderColor,
+    borderRadius,
+  ] = await Promise.all([
+    g("color_primary", "#f59e0b"),
+    g("color_background", "#f8fafc"),
+    g("color_surface", "#ffffff"),
+    g("color_dropdown", "#ffffff"),
+    g("color_navbar", "#ffffff"),
+    g("color_navbar_text", "#1e293b"),
+    g("color_text", "#0f172a"),
+    g("color_text_muted", "#64748b"),
+    g("color_accent", "#10b981"),
+    g("button_primary_color", "#f59e0b"),
+    g("button_text_color", "#1e293b"),
+    g("border_color", "#eeb425"),
+    g("border_radius", "12"),
+  ]);
+
+  // Only hex/keyword color values are admin-controlled — sanitize defensively.
+  const safe = (v: string | null, d: string) => (v && /^[#a-zA-Z0-9(),.\s%-]+$/.test(v) ? v : d);
+
+  const css = `:root{
+--color-primary:${safe(primary, "#f59e0b")};
+--color-background:${safe(background, "#f8fafc")};
+--color-surface:${safe(surface, "#ffffff")};
+--color-dropdown:${safe(dropdown, "#ffffff")};
+--color-navbar:${safe(navbar, "#ffffff")};
+--color-navbar-text:${safe(navbarText, "#1e293b")};
+--color-text:${safe(text, "#0f172a")};
+--color-text-muted:${safe(textMuted, "#64748b")};
+--color-accent:${safe(accent, "#10b981")};
+--button-color:${safe(buttonColor, "#f59e0b")};
+--button-text-color:${safe(buttonText, "#1e293b")};
+--border-color:${safe(borderColor, "#eeb425")};
+--border-radius:${/^\d+$/.test(borderRadius ?? "") ? borderRadius : "12"}px;
+}`;
+
+  // biome-ignore lint/security/noDangerouslySetInnerHtml: server-built CSS from sanitized admin settings
+  return <style dangerouslySetInnerHTML={{ __html: css }} />;
+}