fix(clients): récupère les logos distants en local et sert via le CDN

- Télécharge les logos de kaubuntu.com, kaubuntu.re et kbm.gp
- Les place dans src/assets/images/clients/
- Met à jour les JSON FR/EN pour utiliser les chemins locaux
- Applique le filtre cdn dans le template clients.njk

src/_data/i18n/en/clients.json

@@ -8,21 +8,21 @@
       "name": "KA UBUNTU",
       "domain": "kaubuntu.com",
       "url": "https://kaubuntu.com",
-      "logo": "https://kaubuntu.com/wp-content/uploads/2026/04/logo-ka-ubuntu.png",
+      "logo": "/assets/images/clients/kaubuntu-com.png",
       "description": "Pan-Africanist and pro-independence political movement from Réunion. Fighting for the self-determination of Réunion and African unity. \"I am because we are.\""
     },
     {
       "name": "KA UBUNTU — Media hub",
       "domain": "kaubuntu.re",
       "url": "https://kaubuntu.re",
-      "logo": "https://kaubuntu.re/img/logo.png",
+      "logo": "/assets/images/clients/kaubuntu-re.png",
       "description": "Centralised media aggregator for Ka Ubuntu: YouTube videos, articles, Instagram and TikTok brought together on a single page. Progressive web application (PWA)."
     },
     {
       "name": "KBM – Ka Pou Nou Bwè é Manjé",
       "domain": "kbm.gp",
       "url": "https://kbm.gp",
-      "logo": "https://kbm.gp/images/logo-1024.webp",
+      "logo": "/assets/images/clients/kbm.gp.webp",
       "description": "Movement for the emancipation and food sovereignty of the Guadeloupean people. Community radio Radyo Bòkaz, podcasts, lakou and local farming."
     }
   ]