Recon network batch 2: fleet relay scan and UDP hints.

POST /api/v1/recon/relay-scan probes from the dashboard when reachable, otherwise dispatches recon_relay_scan to a same-/24 online agent. Agents reuse probePortsFn for TCP and optionally UDP 53/51820 with dns/wireguard Path Tracer tags.

server/web/src/types/recon.ts

@@ -160,6 +160,10 @@ export interface ReconScanReport {
   scanned_at: string;
   ports: ReconPortResult[];
   crawl?: ReconCrawlReport;
+  relay_via?: string;
+  udp_hints?: { port: number; open: boolean; service?: string }[];
+  path_tracer_hints?: string[];
+  message?: string;
   recommendations?: ReconDeployRecommendation[];
 }