Apply an automatic dark theme to plots in dark themes

[jmcphers]

Quick little airplane feature to make plots in Positron's Plots pane (and editors) automatically turn dark in dark themes. It's intended for exploratory data analysis, wherein you're not preparing plots for publication but just using them as a visualization tool.

Screen.Recording.2025-02-10.at.8.32.50.AM.mov

Because I expect that this feature will be somewhat polarizing, it is controlled by a explicit configuration setting rather than an implicitly saved preference. You can turn it off at user level, workspace level, etc. in Settings.

Addresses #6255.

Release Notes

New Features

• Optionally apply a color filter to plots in dark mode for automatic theming (Automatic dark filter for plots #6255)

Bug Fixes

• N/A

QA Notes

It is possible to change the dark filter mode right on the Plots pane by clicking the color mode drop down. Note however that this only changes it temporarily! If you want the change to stick (across reloads, etc.) you need to do that in Settings. Changing the value in Settings should cause the UI to react appropriately.

I briefly considered having the dropdown update the setting for you but there's really too much guessing there (did you mean to turn it off for all projects? just this one? etc.)

Test tags: @:plots

[github-actions]

E2E Tests 🚀
This PR will run tests tagged with: @:critical @:plots

^{readme  valid tags}

[timtmok]

Nice!

We will soon need a different way, like a menu or scrolling, to handle the number of buttons.

[jmcphers]

We will soon need a different way, like a menu or scrolling, to handle the number of buttons.

You're right. I think a few of these can be grouped; almost refactored this so that filmstrip mode and color filter were in a new settings 'view options' group.