UniConfig catalog entry

Added the product to src/lib/apps-catalog.ts (idea slug uniconfig) and a logo under public/apps/logos/uniconfig.svg. News post records the first public cut. Deep docs live in the uniconfig Antora component, not in this marketing repo. scripts/spa-fallback.mjs now copies root index.html under /ideas/<slug>/ for every slug in apps-catalog.ts (GitHub Pages has no SPA router). uniconfig.tsx is a file route as a second breadcrumb.