feat: TreeView + VoicesNodeMenu

[damian-molinski]

Description

This is simple implementation of TreeView which supports only one level of depth.
Reasoning here is that google has their package two_dimensional_scrollables which has TreeView implemented but at the moment it's bugged and we can not used it. It's also Scrollable so we need to specify height, which is not ideal.

Related Issue(s)

Closes #733

Screenshots

VoicesTreeView.mov

Related Pull Requests

Part of #719, #729

Please confirm the following checks

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream module

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 177/177}$ | ${\color{red}Fail: 0/177}$ |

[dtscalac]

lgtm