Revisit Plotly.js compatibility with strict CSP

https://github.com/plotly/plotly.js/pull/7109 was added in to make Plotly.js work better in strict CSP environments (specifically, ones which disallow inline CSS); however, it seems some of that work was broken by the migration to ESBuild.

For example, we no longer produce a separate plotly.css file (see recent comments on that PR).

@camdecoster recently added #7527 which makes it easier to test different CSPs in the devtools.

There's at least one obvious issue when inline styles are disallowed, which is that the modebar button styling is completely broken:

まず PR #7109 とその最近のコメントを確認し、次に ESBuild への移行と issue #7527 の CSP テスト設定を調査します。Inline CSS が許可されていない場合に modebar ボタンのスタイリングが失敗する問題を再現し、別個の plotly.css ファイルが生成されるか確認します。厳格な CSP 環境で modebar のスタイリングが正常に機能し続け、関連する build 出力が検証されれば完了です。