Improve Course Editing Workflow with Global Submit Button and Redirect

Currently, when editing a course, only the first section has a visible "Submit" button, limiting the ability to save all changes made across the entire page. There is no general "Submit" option that allows users to save all edits in one action. Additionally, after submitting, the user is not redirected to the course home or overview page.

To improve usability and streamline the editing experience, implement the following enhancements:

Add a global "Submit" button that saves all edits made on the course editing page.

After submitting, automatically redirect the user to the course overview (home) page.

コース編集ページから始め、最初のセクションにある既存の Submit ボタンが変更を保存する仕組みを確認します。現在の送信フローとコース概要のルートを追跡します。完了条件は、1つのグローバルな Submit アクションですべてのページ編集を保存し、概要ページへリダイレクトすることです。