config file loading and saving

js/configPreload.js

@@ -0,0 +1,7 @@
+const { contextBridge, ipcRenderer } = require('electron/renderer')
+
+contextBridge.exposeInMainWorld('electronAPI', {
+    save: (configData) => ipcRenderer.send('save-config', configData),
+    cancel: () => ipcRenderer.send('cancel-config'),
+    onUpdate: (callback) => ipcRenderer.on('update-config', (_event, configData) => callback(configData))
+});