feat: afficher l'équivalent DU pour le volume total et la moyenne de transaction

- SubsquidAdapter : fetchCurrentUD() interroge universalDividends (fallback 11.78 Ğ1)
- DataService : getCurrentUD() avec cache 1h, inclus dans DataResult
- StatsPanel : formatDU() + affichage "≈ X DU" sous le volume total
  et "≈ X Ğ1 / tx · ≈ Y DU / tx" sous le compteur de transactions
- DU actuel Ğ1v2 : 11.78 Ğ1 (bloc 225874)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.tsx

@@ -17,6 +17,7 @@ export default function App() {
   const [refreshing, setRefreshing] = useState(false);
   const [lastUpdate, setLastUpdate] = useState<Date | null>(null);
   const [source, setSource] = useState<'live' | 'mock'>('mock');
+  const [currentUD, setCurrentUD] = useState<number>(11.78);
 
   const animation = useAnimation(transactions, periodDays);
 
@@ -32,11 +33,12 @@ export default function App() {
       if (showLoading) setLoading(true);
       else setRefreshing(true);
       fetchData(periodDays)
-        .then(({ transactions, stats, source }) => {
+        .then(({ transactions, stats, source, currentUD }) => {
           if (!cancelled) {
             setTransactions(transactions);
             setStats(stats);
             setSource(source);
+            setCurrentUD(currentUD);
             setLastUpdate(new Date());
           }
         })
@@ -68,6 +70,7 @@ export default function App() {
         loading={loading}
         periodDays={periodDays}
         source={source}
+        currentUD={currentUD}
         animationLabel={animation.active ? (animation.currentFrame?.label ?? undefined) : undefined}
       />
 

src/components/StatsPanel.tsx

@@ -6,6 +6,7 @@ interface StatsPanelProps {
   loading: boolean;
   periodDays: number;
   source: 'live' | 'mock';
+  currentUD: number;
   animationLabel?: string;
 }
 
@@ -25,7 +26,14 @@ function StatCard({ label, value, sub, delta }: { label: string; value: string;
   );
 }
 
-export function StatsPanel({ stats, loading, periodDays, source, animationLabel }: StatsPanelProps) {
+function formatDU(g1: number, ud: number): string {
+  const du = g1 / ud;
+  if (du < 10)  return `≈ ${du.toFixed(2)} DU`;
+  if (du < 100) return `≈ ${du.toFixed(1)} DU`;
+  return `≈ ${Math.round(du).toLocaleString('fr-FR')} DU`;
+}
+
+export function StatsPanel({ stats, loading, periodDays, source, currentUD, animationLabel }: StatsPanelProps) {
   const periodLabel = periodDays === 1 ? '24 dernières heures' : `${periodDays} derniers jours`;
   const prevStats = useRef<PeriodStats | null>(null);
 
@@ -89,12 +97,16 @@ export function StatsPanel({ stats, loading, periodDays, source, animationLabel
           <StatCard
             label="Volume total"
             value={`${stats.totalVolume.toLocaleString('fr-FR', { maximumFractionDigits: 2 })} Ğ1`}
+            sub={formatDU(stats.totalVolume, currentUD)}
             delta={prevVolume !== null ? (stats.totalVolume > prevVolume ? 'up' : stats.totalVolume < prevVolume ? 'down' : null) : null}
           />
           <StatCard
             label="Transactions"
             value={stats.transactionCount.toLocaleString('fr-FR')}
-            sub={`≈ ${(stats.totalVolume / (stats.transactionCount || 1)).toFixed(2)} Ğ1 / tx`}
+            sub={(() => {
+              const avg = stats.totalVolume / (stats.transactionCount || 1);
+              return `≈ ${avg.toFixed(2)} Ğ1 / tx  ·  ${formatDU(avg, currentUD)} / tx`;
+            })()}
             delta={prevTxCount !== null ? (stats.transactionCount > prevTxCount ? 'up' : stats.transactionCount < prevTxCount ? 'down' : null) : null}
           />
           {/* Couverture géo — uniquement en mode live */}

src/services/DataService.ts

@@ -12,7 +12,7 @@
  * Pour activer : définir VITE_USE_LIVE_API=true dans .env.local
  */
 
-import { fetchTransfers, buildIdentityKeyMap } from './adapters/SubsquidAdapter';
+import { fetchTransfers, buildIdentityKeyMap, fetchCurrentUD } from './adapters/SubsquidAdapter';
 import { resolveGeoByKeys } from './adapters/CesiumAdapter';
 import {
   getTransactionsForPeriod,
@@ -22,6 +22,16 @@ import {
 
 const USE_LIVE_API = import.meta.env.VITE_USE_LIVE_API === 'true';
 
+// Cache du DU courant, valide 1 heure (le DU change tous les ~6 mois)
+let udCache: { value: number; expiresAt: number } | null = null;
+
+async function getCurrentUD(): Promise<number> {
+  if (udCache && Date.now() < udCache.expiresAt) return udCache.value;
+  const value = await fetchCurrentUD();
+  udCache = { value, expiresAt: Date.now() + 60 * 60 * 1000 };
+  return value;
+}
+
 // Cache de la carte identité SS58→DuniterKey, valide 10 minutes
 let keyMapCache: { map: Map<string, string>; expiresAt: number } | null = null;
 
@@ -106,6 +116,7 @@ export interface DataResult {
   transactions: Transaction[];  // uniquement géolocalisées → heatmap
   stats:  PeriodStats;
   source: 'live' | 'mock';
+  currentUD: number; // valeur du DU courant en Ğ1
 }
 
 export async function fetchData(periodDays: number): Promise<DataResult> {
@@ -117,10 +128,14 @@ export async function fetchData(periodDays: number): Promise<DataResult> {
       transactions,
       stats: { ...base, geoCount: transactions.length },
       source: 'mock',
+      currentUD: 11.78,
     };
   }
 
-  const { geolocated, totalCount, totalVolume } = await fetchLiveTransactions(periodDays);
+  const [{ geolocated, totalCount, totalVolume }, currentUD] = await Promise.all([
+    fetchLiveTransactions(periodDays),
+    getCurrentUD(),
+  ]);
   const base = computeStats(geolocated);
 
   return {
@@ -132,5 +147,6 @@ export async function fetchData(periodDays: number): Promise<DataResult> {
       topCities: base.topCities,
     },
     source: 'live',
+    currentUD,
   };
 }

src/services/adapters/SubsquidAdapter.ts

@@ -153,6 +153,27 @@ export async function buildIdentityKeyMap(): Promise<Map<string, string>> {
   return result;
 }
 
+/** Retourne la valeur du DU courant en Ğ1 (ex : 11.78). Fallback hardcodé si indisponible. */
+export async function fetchCurrentUD(): Promise<number> {
+  const UD_FALLBACK = 11.78; // valeur au bloc 225874 — mis à jour si la requête échoue
+  try {
+    const response = await fetch(SUBSQUID_ENDPOINT, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        query: `{ universalDividends(orderBy: BLOCK_NUMBER_DESC, first: 1) { nodes { amount } } }`,
+      }),
+    });
+    if (!response.ok) return UD_FALLBACK;
+    const raw = await response.json();
+    const amountStr: string | undefined = raw?.data?.universalDividends?.nodes?.[0]?.amount;
+    if (!amountStr) return UD_FALLBACK;
+    return parseInt(amountStr, 10) / 100;
+  } catch {
+    return UD_FALLBACK;
+  }
+}
+
 export interface FetchTransfersResult {
   transfers: RawTransfer[];
   totalCount: number;