Show services discovered by site agents as suggested targets

Stores the sanitised list per site, serves it at /sites/{id}/discovered and adds
it to the target picker. Needs a Reef release containing model.DiscoveredService.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

infra.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"net"
 	"net/http"
+	"net/netip"
 	"sort"
 	"strings"
 	"time"
@@ -291,6 +292,47 @@ func (s *Server) siteContainers(w http.ResponseWriter, r *http.Request, c *orgCt
 	writeJSON(w, 200, out)
 }
 
+// cleanDiscovered keeps what an agent reports as suggestions only if it is well formed: it is shown in
+// the dashboard, so lengths are bounded and anything that is not a plain address is dropped.
+func cleanDiscovered(in []model.DiscoveredService) []model.DiscoveredService {
+	out := []model.DiscoveredService{}
+	clip := func(s string, n int) string {
+		if len(s) > n {
+			s = s[:n]
+		}
+		return strings.ToValidUTF8(s, "")
+	}
+	for _, d := range in {
+		if len(out) >= 500 {
+			break
+		}
+		if _, err := netip.ParseAddr(d.Host); err != nil || d.Port < 1 || d.Port > 65535 {
+			continue
+		}
+		src := "scan"
+		if d.Source == "local" {
+			src = "local"
+		}
+		out = append(out, model.DiscoveredService{Host: d.Host, Port: d.Port, Proto: "tcp", Service: clip(d.Service, 20), Detail: clip(d.Detail, 160), Source: src})
+	}
+	return out
+}
+
+func (s *Server) siteDiscovered(w http.ResponseWriter, r *http.Request, c *orgCtx) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	st := s.findSite(r.PathValue("id"))
+	if st == nil || !s.siteVisible(c, st) {
+		fail(w, 404, errors.New("no such site"))
+		return
+	}
+	out := s.discovered[st.ID]
+	if out == nil {
+		out = []model.DiscoveredService{}
+	}
+	writeJSON(w, 200, out)
+}
+
 // ---------- domains ----------
 
 func domainsOverlap(a, b string) bool {