fix: replace emoji flags with text badges, clean city names from postal codes

Emoji flags render as boxes on Linux. Replace with a small FR/BE/CH
badge. Also strip postal codes from Cesium+ city names (e.g.
"Saint-Jean-de-Laur, 46260" → "Saint-Jean-de-Laur").

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

src/services/adapters/CesiumAdapter.ts

@@ -50,12 +50,9 @@ function latLngToCountryCode(lat: number, lng: number): string {
   return '';
 }
 
-/** Convertit un code ISO 3166-1 alpha-2 en emoji drapeau */
-export function countryCodeToFlag(code: string): string {
-  if (!code || code.length !== 2) return '';
-  return String.fromCodePoint(
-    ...code.toUpperCase().split('').map((c) => 0x1F1E0 - 65 + c.charCodeAt(0))
-  );
+/** Nettoie le nom de ville Cesium+ : retire le code postal ("Paris, 75001" → "Paris") */
+export function cleanCityName(city: string): string {
+  return city.split(',')[0].trim();
 }
 
 // geoPoint accepte n'importe quel type — Cesium+ utilise plusieurs formats ES geo_point
@@ -132,7 +129,7 @@ export async function resolveGeoByKeys(
     if (!geo) continue;
     result.set(hit._id, {
       name:        src.title ?? '',
-      city:        src.city ?? 'Inconnue',
+      city:        cleanCityName(src.city ?? 'Inconnue'),
       countryCode: latLngToCountryCode(geo.lat, geo.lng),
       lat:         geo.lat,
       lng:         geo.lng,