“Prüfen” button next to API key field — auto-fills the registered federation and club, locks them for free/pro keys (federation tier still has full freedom). Lock now persists across saves (15-min transient cache, server-side rendered)
Fixed critical PHP TypeError when saving settings without selecting all fields (sanitize callbacks now accept null/empty values)
New “Transparent background” option (transparent=”1″ shortcode attribute) — widget background becomes transparent so the host page background shows through; theme (light/dark/auto) still drives text and border colours
New API endpoint /api/v1/key-info returns tier, federation and registered club for the calling key
