refactor: import brand icons directly from design system

Import PNGs via Vite from @cameleer/design-system/assets instead of
copying to public/. Only favicons remain in public/ (needed by HTML).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-app/src/main/java/com/cameleer3/server/app/security/SecurityConfig.java

@@ -95,8 +95,6 @@ public class SecurityConfig {
                                 "/index.html",
                                 "/config.js",
                                 "/favicon-*.png",
-                                "/cameleer3-logo-*.png",
-                                "/camel-logo.svg",
                                 "/assets/**"
                         ).permitAll()