WIP feat(APP-3795): Implement expandedActions override for better actions builder UX

[thekidnamedkd]

Description

Leverage unique values for action items to override expanded actions so that

• If a new action is added, expand it and collapse all others.
• If multiple actions have existed, but all are removed except one, leave the last one expanded.
• When there are no children, cleanup expanded actions with reset.

Task: APP-3795

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• Manually smoke tested the functionality locally
• Confirmed there are no new warnings or errors in the browser console
• Made the corresponding changes to the documentation
• Added tests that prove my fix is effective or that my feature works
• Updated the CHANGELOG.md file after the [UPCOMING] title and before the latest version
• (For User Stories only) Double-checked that all Acceptance Criteria are satisified
• Confirmed there are no new warnings on automated tests
• Selected the correct base branch
• Commented the code in hard-to-understand areas
• Followed the code style guidelines of this project
• Reviewed that the files changed in GitHub’s UI reflect my intended changes
• Confirmed the pipeline checks are not failing