v0.281.0: 'Done' asks the probe first; sign-up closed after the first admin (decision 47); R-713 code-bound values refused, ${NAME|base64}

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/handlers.go

@@ -774,6 +774,16 @@ func (s *Server) appDetailHandler(w http.ResponseWriter, r *http.Request, slug s
 	// v0.280.0 (decision 46): the setup gate's card, while the gate stands.
 	data["SetupGateClosed"] = found.Deployed && found.AppConfig != nil && found.AppConfig.SetupGate.Closed()
 	data["SetupGateHasProbe"] = found.Meta.SetupDoneProbe != nil && found.Meta.SetupDoneProbe.URL != ""
+	// v0.281.0 (decision 47): the sign-up card — closed, or open for the household's 15 minutes.
+	if s.stackMgr != nil {
+		blocked, until := s.stackMgr.SignupBlocked(found.Name)
+		data["SignupClosed"] = blocked
+		if until != "" {
+			if t, err := time.Parse(time.RFC3339, until); err == nil {
+				data["SignupOpenUntil"] = t.In(getTimezone()).Format("15:04")
+			}
+		}
+	}
 	data["HasAppInfo"] = found.Meta.HasAppInfo()
 	data["EffectiveSubdomain"] = effectiveSubdomain