[w-engine][FEATURE] Allow setting one wallpaper for all monitors

[vivien-delta]

Submission checklist

• I have searched existing issues and confirmed this has not been requested before.
• I have checked existing pull requests for similar changes.
• This is about a community plugin, not about Noctalia itself (those belong in the noctalia repo).

Plugin

w-engine

Feature type

Configuration / customization

Feature summary

An ability to toggle between setting one wallpaper for all monitors or multiple on a per-monitor basis.

Motivation / use case

I have two monitors and am considering buying another. I will never have their backgrounds differ across my displays. I do appreciate multi-monitor selection as the baseline, but setting two (potentially more) wallpapers every time I do layout changes is something I find very cumbersome, especially since it means palettes will not always generate for Noctalia depending on which monitor I choose first.

Proposed solution

Currently, W-Engine has a dropdown menu to select which monitor you'd like to place the wallpaper on. I think a separate section titled All that sets the flags for every one, even if the update is asynchronous due to pushing multiple commands, would be the best way to go about this.

Alternatives considered

No response

References / related projects

jagrat7's linux-wallpaper-engine-ux project has this functionality.

Additional context

No response

[github-actions]

CC @Tadomika-Ari

[Tadomika-Ari]

Hi,
I’m currently working on my other plugin, Config Swap, but this feature is already planned for the next update, which should be out very soon. (Probably within the week)

[vivien-delta]

Awesome. Thank you for the hard work!