[enhancement] 从github直接搜索和下载应用

[tumuyan]

新功能

1. 无需订阅源，直接利用github的搜索/收藏/访问页面，获得一组应用
2. 解析github release页面自动获取release版本的apk文件
3. 解析github action获取自动构建的测试版软件（这个方法存在一些问题，github action需要登录帐号才能下载，并且build不一定有结果，build结果很可能并非可以直接安装的格式）

添加该功能的原因

去除他人干预地获取应用，更自由，也更便利

实现方法或步骤

待定

[xz-dev]

@tumuyan 1. 源代表着不同的网站解析方式，所以这个无论如何都是必要的
2. 这个正在做
3. 这个需要服务端的后续开发

[tumuyan]

@tumuyan 1. 源代表着不同的网站解析方式，所以这个无论如何都是必要的

我的想法是，不需要更新hub，不需要人工维护每一个应用，就可以直接查看一个软件列表，或者直接搜索。当然如果网站API变化了，解析器是需要更新的

[xz-dev]

@tumuyan 目前可以你自己填写你希望的 URL，并不是像包管理器那样有一个固定的数据库。发现界面的列表只是方便用户下载/更新/分享已有的配置。

[tumuyan]

所以如果需要添加应用，需要在编辑跟踪项页面粘贴每每一个应用的url。
这不是不可接受，但是如果有一个批量验证并添加的功能，操作会更加方便。

[momobobe]

I second this.

For Item 1, I guess OP meant to make more work done on the client side, rely less on remote server, aka enhance capability of local crawling. I think it's a good idea to add an option (up to the user's preferrence) to ensure only direct connection to update sources should be made during using UpgradeAll, unless user triggered update for rule, for the sake of privacy and robustness.

For Item 2, source code for Izzy's repo may provide some inspiration. It does something very similar like your project, to download APKs from GitHub, GitLab, fixed link, etc, although it runs on a server. The biggest problem for that project is, Izzy decides everything and has refused a lot of Apps for inclusion, and that's why I found this project of great potential. As a user, I just want a solution to finish everything about updating Apps downloadable from GitHub solely on my Android device, without intermediate server (server for rule subscription is acceptable though).

As for Item 3, maybe it's a little too complex as OP suggested, but if you wanna try, maybe nightly.link is good project for reference, which provides download for GitHub Actions build artifacts.

Also for OP's supplement, it must be very appealing if able to export & import custom list provided by users and editable outside the App, which would be very convenient to share and maintain.

More of my ideas are expanded in #175.