ADD: Basic save

src/preload/index.d.ts

@@ -7,6 +7,7 @@ export interface INanoDevicesAPI {
     callback: (eventid: string, deviceid: string, data: any) => void
   ): void
   send(deviceid: string, jsonstr: string): Promise<void>
+  save(deviceid: string): Promise<void>
 }
 
 export interface IElectronAPI {

src/preload/index.ts

@@ -22,6 +22,9 @@ contextBridge.exposeInMainWorld('nanoDevicesAPI', {
   },
   send(deviceid, obj) {
     return ipcRenderer.invoke('nanodevices:send', deviceid, JSON.stringify(obj))
+  },
+  save(deviceid) {
+    return ipcRenderer.invoke('nanodevices:send', deviceid, JSON.stringify({ save: true }))
   }
 })