B6 fixes from first E2E contact: PUT /probe/notify answers the fresh view; frontend notifyLogin is boolean and secret flags use the notify-prefixed wire names

internal/web/controller/probe_notify.go

@@ -55,7 +55,12 @@ func (pc *ProbeNotifyController) put(c *gin.Context) {
 		c.JSON(http.StatusOK, entity.Msg{Success: false, Msg: err.Error()})
 		return
 	}
-	jsonMsg(c, "", nil)
+	// Answer with the fresh view, like the GET: the tab re-renders
+	// the channel status and secret-set flags from it.
+	jsonObj(c, probeNotifyPayload{
+		Settings: probenotify.GetSettings(),
+		Coverage: service.ProbeAgentCoverage(),
+	}, nil)
 }
 
 func (pc *ProbeNotifyController) test(c *gin.Context) {