feat: indicateurs de statut et configuration des endpoints SubSquid/Cesium+

- Dots de statut en temps réel dans le StatsPanel (ok/slow/error + latence)
- Bannière d'alerte si un service est inaccessible
- EndpointPopover : sélection parmi nœuds connus, test de latence live, URL custom
- Rechargement automatique des données après changement d'endpoint
- SubsquidAdapter et CesiumAdapter lisent l'URL active depuis EndpointConfig
- InfoPanel mis à jour (overlay DU + statut des services)

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

src/components/StatsPanel.tsx

@@ -2,6 +2,8 @@ import { useRef } from 'react';
 import type { PeriodStats } from '../services/DataService';
 import type { FlowStats } from '../data/arcData';
 import { Sparkline } from './Sparkline';
+import { ServiceStatusDots } from './ServiceStatusDots';
+import { useServiceStatus } from '../hooks/useServiceStatus';
 
 interface StatsPanelProps {
   stats: PeriodStats | null;
@@ -15,6 +17,7 @@ interface StatsPanelProps {
   flowStats?: FlowStats | null;
   focusCity?: string | null;
   onClose?: () => void;
+  onEndpointChange?: () => void;
   allTimestamps?: number[];
 }
 
@@ -62,7 +65,8 @@ function CityRow({ city, volume, count, countryCode, accent }: {
   );
 }
 
-export function StatsPanel({ stats, loading, periodDays, source, currentUD, animationLabel, viewMode = 'heatmap', flowStats, focusCity, onClose, className, allTimestamps = [] }: StatsPanelProps) {
+export function StatsPanel({ stats, loading, periodDays, source, currentUD, animationLabel, viewMode = 'heatmap', flowStats, focusCity, onClose, onEndpointChange, className, allTimestamps = [] }: StatsPanelProps) {
+  const { subsquid, cesium, recheck } = useServiceStatus();
   const periodLabel = periodDays === 1 ? '24 dernières heures' : `${periodDays} derniers jours`;
   const prevStats = useRef<PeriodStats | null>(null);
 
@@ -97,7 +101,11 @@ export function StatsPanel({ stats, loading, periodDays, source, currentUD, anim
             Ğ1Flux
             <span className="text-[#4b5563] text-xs font-normal ml-1.5">v{__APP_VERSION__}</span>
           </h1>
-          <p className="text-[#4b5563] text-xs">Monnaie libre · Flux géo</p>
+          <ServiceStatusDots
+            subsquid={subsquid}
+            cesium={cesium}
+            onEndpointChange={() => { recheck(); onEndpointChange?.(); }}
+          />
         </div>
         {onClose && (
           <button