The catalog pointed at a non-existent nostr.svg (handleImageError only falls
back .png→.svg, so an .svg miss stays broken). Point it at the existing nostr
icon. fedimint icon already uses fedimint.png (exists); the stale fedimint.jpg
request is resolved by /api/app-catalog now serving the local catalog.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>