chore: upgrade to 10.8.0+26.6.3

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

compose.yml

@@ -1,6 +1,6 @@
 services:
   app:
-    image: "keycloak/keycloak:26.6.2"
+    image: "keycloak/keycloak:26.6.3"
     entrypoint: >
       bash -c "KEYCLOAK_ADMIN_PASSWORD=\"$$(cat /run/secrets/admin_password)\" KC_DB_PASSWORD=\"$$(cat /run/secrets/db_password)\" /opt/keycloak/bin/kc.sh start"
     networks:
@@ -48,10 +48,10 @@ services:
         - "caddy=${DOMAIN}"
         - "caddy.reverse_proxy={{upstreams 8080}}"
         - "caddy.tls.on_demand="
-        - "coop-cloud.${STACK_NAME}.version=10.7.1+26.6.2"
+        - "coop-cloud.${STACK_NAME}.version=10.8.0+26.6.3"
 
   db:
-    image: "mariadb:12.2"
+    image: "mariadb:12.3"
     environment:
       - MYSQL_DATABASE=keycloak
       - MYSQL_USER=keycloak