Refactor/api folder structure

[HinsonSIDAN]

Summary

There is no logic code change in this PR. All changes in application code only due to eslint and prettier rules as configured. This PR refactors the code base to be more collab-friendly, adding

1. Eslint and prettier coding basis (Issue Extract types into its own file #9)
2. Commitlint (Issue Extract types into its own file #9)
3. Splitting api into a readable folder structure (Issue Add code style checking and formatting #16)

Type of Change

Please mark the relevant option(s) for your pull request:

• [ X ] Code refactoring (improving code quality without changing its behavior)

Additional Information

I just pasted the usual linting I used for other projects. Please feel free to adjust to the one more "Maestro-standard". There are some linting erroor as I plug it in, and currently i disabled them for passing the linting check at commit. See if you guys want to turn it back on:

.eslintrc

    "rules": {
        "class-methods-use-this": "off",
        "prefer-regex-literals": "warn",
        "no-control-regex": "warn",
        "no-use-before-define": "warn",
        "no-param-reassign": "warn",
        "max-classes-per-file": "warn",
        "no-useless-constructor": "off"
    }

[Vardominator]

Thanks for the massive contribution!