[IMPROVEMENT] Improve project explorer look and feel

[Buster-Darragh-Major]

Description

The project window, while more or less functionally complete has a very rough look and feel. To improve user experience it would be nice to perhaps be able to distinguish between files and directories a little better and make the back button look a little nicer/obvious. Observe the current state of the project explorer to see what I mean.

For reference, it would be nice to have the look and feel fit with the current aesthetic made by @encryptededdy. See below.

Acceptance Criteria

1. Back button fits with the look and feel of the rest of the application
2. Files and folders are distinguished by more than just font boldness.

[rmberriman]

Approved - would be a nice improvement to UX

[hhagenson28]

Agree, would be good for UI to be more consistent - approved

[Jess-Alcantara]

Approved!