v0.1.2

Add self-update flow, multi-platform release assets, and release v0.1.2

- add interactive release checking and manual --update flow
- cache GitHub release metadata for throttled update prompts
- replace curl downloads with built-in Rust HTTP requests
- support Linux x86_64, Linux arm64, and macOS arm64 release assets
- expand GitHub Actions release workflow to build and publish all supported archives
- update English and Chinese README installation and platform notes
- bump crate version to 0.1.2

新增自更新流程、多平台发布产物并发布 v0.1.2

- 增加交互式版本检查与手动 --update 更新流程
- 缓存 GitHub Release 元数据，用于节流更新提示
- 使用 Rust 内置 HTTP 请求替换 curl 下载
- 支持 Linux x86_64、Linux arm64、macOS arm64 发布产物
- 扩展 GitHub Actions release workflow，构建并发布所有支持平台压缩包
- 更新中英文 README 的安装与平台说明
- 将 crate 版本提升到 0.1.2