feat(macro-vibes): rename BTC Signal → Macro Vibes; add MacroPanel UI

Module rename across page H1, navbar tab, URL (/en/btc → /en/macro),
all metadata/JSON-LD, sitemap, llms.txt, opengraph image, and SystemControl
copy. Old /btc route fully removed.

New components/btc/MacroPanel.tsx polls /api/macro/snapshot and lays out
the 8 indicators in four sections (Valuation / Bottom trigger reference /
Market structure / Sentiment & flows / Positioning) with tone-coloured
values, current-band threshold chips, and a single CoinGlass / source
chart link per card. Composite -100..+100 needle pulses on score change.

Also fixes the pinned bottom-reversal alert on the homepage, which still
linked to the now-404 /en/btc — now routes to /en/macro.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/opengraph-image.tsx

@@ -86,7 +86,7 @@ export default function OGImage() {
         >
           {[
             { label: 'Trump · Truth Social', color: '#f5a524' },
-            { label: 'BTC Bottom Reversal', color: '#a78bfa' },
+            { label: 'Macro Vibes', color: '#a78bfa' },
             { label: 'KOL Signal', color: '#22c55e' },
             { label: 'Talks vs Trades', color: '#ef4444' },
           ].map((p) => (