feat(seo/geo): Dataset + Article + BreadcrumbList structured data, noindex archive

GEO (AI answer engines) — make the signal feeds and case studies machine-citeable:
- Dataset JSON-LD on /trump, /kol, /trades (creator=Endorphin, publisher→#org,
  isAccessibleForFree, temporalCoverage). These are the "data/history/track
  record" entities Perplexity/Gemini/ChatGPT cite.
- case-studies: ItemList of 5 Article nodes, each with headline/description/
  articleBody/about + citation→evidence URL + author=Endorphin. ISO dates
  derived where parseable, omitted for vague labels.
- public/llms-full.txt: single-doc full reference (methodology + glossary +
  case studies w/ sources inlined) for one-fetch AI ingestion; linked from llms.txt.

SEO:
- Breadcrumbs component (components/seo/Breadcrumbs.tsx) → BreadcrumbList JSON-LD
  on the 8 indexable content pages (trump/kol/macro/trades/analytics/
  methodology/glossary/case-studies).
- /archive split into server page + ArchivePageClient; server page sets
  robots noindex (legacy/test data — thin-content risk).
- openGraph added to /trades and /analytics (previously meta+canonical only).

Verified: tsc 0 errors, next build passes, runtime curl confirms all JSON-LD
types render and llms-full.txt serves 200. No trading/API/component-logic changes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

components/seo/Breadcrumbs.tsx

@@ -0,0 +1,34 @@
+// Emits a schema.org/BreadcrumbList as JSON-LD. Server-component friendly —
+// renders only a <script> tag, no visible DOM. Helps Google breadcrumb rich
+// results and gives AI answer engines the page's entity hierarchy.
+//
+// Usage (server component):
+//   <Breadcrumbs items={[{ name: 'Methodology', path: '/en/methodology' }]} />
+// "Home" is prepended automatically; pass the page itself as the last item.
+
+const siteUrl = process.env.NEXT_PUBLIC_SITE_URL || 'https://trumpsignal.com'
+
+export interface Crumb {
+  name: string
+  path: string // e.g. "/en/methodology"
+}
+
+export default function Breadcrumbs({ items }: { items: Crumb[] }) {
+  const all: Crumb[] = [{ name: 'Trump Alpha', path: '/en' }, ...items]
+  const jsonLd = {
+    '@context': 'https://schema.org',
+    '@type': 'BreadcrumbList',
+    itemListElement: all.map((c, i) => ({
+      '@type': 'ListItem',
+      position: i + 1,
+      name: c.name,
+      item: `${siteUrl}${c.path}`,
+    })),
+  }
+  return (
+    <script
+      type="application/ld+json"
+      dangerouslySetInnerHTML={{ __html: JSON.stringify(jsonLd) }}
+    />
+  )
+}