- Provide default rtsp://<ip>/ monitor entry for cameras discovered
via ARP that lack a vendor-specific probe function, so they always
have a URL for the Add button
- Only render the Add button and populate ProbeResults when url is
non-empty, preventing the "No url in button" alert
- Fix curl_getinfo() called after curl_close() which broke HTTP
response body parsing in probe functions
- Add missing break in import switch case to prevent fall-through
to default warning
maybe fixes#4613
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>