add safe storage util

src/utils/safeStorage.ts

@@ -0,0 +1,12 @@
+import { safeStorage } from 'electron';
+import { safeStorageStore } from '../services/store';
+
+export function setEncryptionKey(encryptionKey: string) {
+    const buffer = safeStorage.encryptString(encryptionKey);
+    safeStorageStore.set('encryptionKey', buffer.toString('base64'));
+}
+
+export function getEncryptionKey() {
+    const bufferString = safeStorageStore.get('encryptionKey');
+    return safeStorage.decryptString(Buffer.from(bufferString, 'base64'));
+}