Enhance breadcrumbs for file navigation
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### Proposal
My suggestion is to enhance the static breadcrumb that is displayed while navigating a project's files. Specifically, I'd like to see dynamic navigation similar to how the breadcrumbs within Visual Studio Code operate.
Let's imagine the following very simple project structure.
```
- src
|
- components
|
- Header
|
- index.js
- Header.js
- helpers.js
- Body
- Footer
- utils
- package.json
```

If I am currently viewing Header.js, I'd like to be able to click (possibly a new dropdown) a crumb and see the other files/directories at that level and be able to navigate into them directly. It would save time having to navigate back a bunch and down into directories and reduce the constant opening of things in new browser tabs.
Here is a screenshot of how Visual Studio Code would show this scenario.
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