Refactoring

[mizdra]

I must keep the code simple in order to add features and tests. To achieve this, I will implement bold refactoring.

[mizdra]

First, I do minimal refactoring.

• [x] Cut the CLI option parser out of the main function
• [x] Abstracts the check for isDirty

[mizdra]

I decided on an overall refactoring policy.

ref: 2022/7/24 checkable-css-modules/リファクタリングの作戦を考える - mizdra

[mizdra]

Basic refactoring is complete 🎉