Introduce a new SSDP/UPnP network scanner alongside the existing ARP and
mDNS scanners:
- New scanner module under scanners/ssdp (finder, scanner, status)
- Wire the scanner into the main scan loop
- Add Ssdp variant to DeviceEventScanner
- Add SsdpScanner settings with a configurable probe timeout
- Expose /api/ssdp_scanner/status and wire it into OpenAPI generation
- Add a lint.sh helper and point CLAUDE.md at it
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
