chore(config): 配置 npm 镜像源

- 添加 electron 镜像源配置
- 添加 electron_builder 二进制文件镜像源配置
- 设置 registry 为国内镜像源
- 提高依赖包下载速度和稳定性

.npmrc

@@ -0,0 +1,3 @@
+electron_mirror=https://npmmirror.com/mirrors/electron/
+electron_builder_binaries_mirror=https://npmmirror.com/mirrors/electron-builder-binaries/
+registry=https://registry.npmmirror.com