✨ Separate files and folders in the "Open Recent" sub-menu

### Is your feature request related to a problem? Please describe.

If both share the same list, after opening a few files within the same project, other projects will not be found in the menu.

### Describe the solution you'd like

The histories of recently-opened files and folders should be separated, so you can easily switch between projects even if many files were opened recently. This is done by VSCode and other editors. XCode doesn't do this, but XCode only tracks projects/playgrounds, not individual source files.

### Describe alternatives you've considered

n/a

### Additional context