feat: add a function to set theme dynamically

[Legend-Master]

Closes #582
Closes #891

[Legend-Master]

I don't quite understand how ThemeChanged works in tao to be honest, when should it be fired? We currently only fires it when the window's theme is set to auto/no preference and the theme is actually changed
I think it should be fired whenever the theme changes no matter if the theme is set to None or Some(Theme) Never mind, only auto will can have theme changes

I'm not sure how to send events from set_theme, do we do a RegisterWindowMessage and use PostMessage here?

[Legend-Master]

We probably can just mirror the mac and linux implementations from winit (they should be much more straight forward compared to the Windows one 😂), but I can't test them, so I'll just do the Windows one for now

[FabianLars]

Moving my discord message here: The macos implementation worked on my machine. 👍

[github-actions]

Package Changes Through 0b1daad

There are 1 changes which include tao with patch

Planned Package Versions

The following package releases are the planned based on the context of changes in this pull request.

package	current	next
tao	0.30.0	0.30.1

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[Legend-Master]

I don't know if sending WM_SETTINGCHANGE ourselves here is fine or not since the wparam and lparam are actually not 0 from the system one, and by the way, if you do this, you need to set redraw_title_bar to true

[amrbashir]

I don't know if sending WM_SETTINGCHANGE ourselves here is fine or not since the wparam and lparam are actually not 0 from the system one

Doesn't matter since we don't read either of them.

and by the way, if you do this, you need to set redraw_title_bar to true

From my testing, this doesn't seem to be needed.

[Legend-Master]

@amrbashir the windows one is not working right now, you need to set redraw_title_bar to true, see my comment above

[amrbashir]

I guess Windows 10, really needs to redraw, just changed it to always redraw then

[amrbashir]

BTW, sorry for hijacking the PR, I was just testing a few things out and thought might as well push it instead of requesting another review.

[Legend-Master]

All good, feel free to make changes 😃