Depreciating Python 2 / Use pyinstaller/py2app for MacOS builds

As you've probably noticed, the installer breaks fairly often due to making a change which works on Python 3, but which doesn't work on Python 2.

We've been supporting Python 2 for MacOS users, as Python 2 comes pre-installed for them, and we don't want to make them install Python 3 on their system (it would complicate the install process, and also may alter their system setup)

One way around this would be to use a tool like [pyinstaller](https://www.pyinstaller.org/) or [py2app](https://py2app.readthedocs.io/en/latest/) to generate a standalone installer/app which the user can just run. However doing so would probably require quite a bit of testing, as I suspect some things our installer currently does (like writing to a folder adjacent to the executable) will break in this configuration.

While developers on Windows/Linux can't do the builds on their own computers, Github Actions supports MacOS as an environment, so once it's setup properly it should be OK to maintain.

I'm mainly opening this issue in case any MacOS users/developers want to figure out some distribution method for the installer on MacOS. It probably won't happen any time soon, but I thought I should at least make an issue for it.

該 issue 是關於使用 pyinstaller 或 py2app 建立一個獨立的 macOS 安裝程式，以取代目前依賴 Python 2 的安裝程式。首先檢查現有安裝程式程式碼，了解其檔案寫入和執行流程。在 macOS 環境（可能使用 GitHub Actions）中測試使用 pyinstaller 建立一個簡單的獨立應用程式。「完成」意味著一個可運作的獨立安裝程式，不會破壞現有功能，需要對檔案操作進行徹底測試。

由索引模型根據 Issue 內容生成。