Dark mode for @uppy/status-bar

[anthony0030]

Initial checklist

• I understand this is a feature request and questions should be posted in the Community Forum
• I searched issues and couldn’t find anything (or linked relevant results below)

Problem

@uppy/status-bar only has light mode

Solution

Add a a theme option like @uppy/dashboard

Alternatives

I can't think of one.

[Murderlon]

This already exists? Click the "dark mode" checkbox on the examples page.

https://uppy.io/examples/

[anthony0030]

The theming CSS for the status-bar exists, but if you try to use the status-bar outside of the dashboard, you can only use light mode. I took the code implementation from the dashboard component and applied it to the status-bar as well.

[Murderlon]

I understand that's not ideal. The components are a bit in an odd spot where they're tailored made for Dashboard but you can kind of use them without it. The ideal solution is #5379 but that's not planned or prototyped yet.

I'm a bit hesitant to duplicate that logic and option on every single component. It would make sense for @uppy/core to be aware of it and it moves through the plugins with a single source of truth. But that would be a breaking change or awkward backwards compatibility.