TV Show Project Level 300: Swap back to your old codebase

# Level 300

For level 300, you should switch back to your original codebase.

You should have reviewed and merged your partner's level 200 changes through a PR to your own repo.

Remember to pull the latest changes onto your local machine.

Once again, compare their implementation to yours. Think:
1. How is it different?
2. What do you prefer about your implementation?
3. What do you prefer about their implementation?
4. What did you learn that you didn't know before?

Have a discussion about your answers to these questions. In class, together, give a 3 minute talk about your conclusions.

## Refactoring

Like with level 200, feel free to change anything in your codebase which you think will make it easier to work with, or to build new features.

Make a branch and pull request for yourself, and then have your partner review, making sure they understand the changes made.

## Adding new functionality

Level 300 is about getting rid of our static data from `episodes.js`, and instead using an API.

### Requirements

1. You must delete the `episodes.js` file from your repository.
2. Your website must still work the same, but by using a `fetch` request to https://api.tvmaze.com/shows/82/episodes. This URL should serve the exact same content as was returned by `getAllEpisodes` in `episodes.js`.
3. You must fetch this URL only _once_ per visit to your website. You should not re-fetch when someone searches, scrolls, or selects an episode from the drop-down.
4. If you don't have data yet, you should show something to tell the user to wait for the data.
5. If an error occurred loading the data, notify the user.
1. Note: real users don't look in the console - `console.log` or `console.error` are not sufficient for this requirement.
2. You will need to simulate an error to test this out yourself.

### Documentation

You can see that this endpoint has been documented here: https://www.tvmaze.com/api#show-episode-list

episodes.js と既存の getAllEpisodes フローから始め、続いて、ウェブサイトがエピソードデータを検索、スクロール、選択にどのように利用しているかを確認します。TVMaze のエピソード一覧 API のドキュメントを読み、読み込み状態とシミュレートされたエラー状態をテストします。episodes.js が削除され、URL が訪問ごとに一度だけ取得され、ユーザーが待機中またはエラー時に目に見えるフィードバックを受け取れることが完了の条件です。

索引モデルが issue の本文から書いたものです。