system wide color scheme and theme, controlled by nuguland

system theme: dark mode / light mode
color scheme: nugu -> single source of truth for colors, defines palettes for dark and light
nuguland: apply nugu color scheme  based on theme

app types:
- qt apps
- gnome/gtk apps
- terminal
- TUIs and CLIs
- electron

as far as i know, there is no freedesktop system theme standard?
i saw people fall back on gtk and/or qt system theme settings. needs research.

typically, apps support these theming capabilities:
- listen to system theme
- define color scheme
- define color scheme per dark/light
- define colors

also relevant in this context is the different types of config languages for apps:
- static declarative (json, toml, ini,...)
- static declartive, with structure (some kind of "import" directive)
- dynamic (lua, js, ...)


what i wnat to achieve:
- toogle system theme with keybind -> all apps react
- toggle theme based on time of day or position of sun

the challenge: apps fall into vastly different categories and capabilities. it is unclear, how to support all the apps i care about. for reference: other apps like noctalia or wallust edit configuration files of supported apps. that may be the only way, but it annoys me, that i see changes in git of dotfiles, just because theme switched.
the good news: the way i handle CLI and TUI apps, almost always depends on wezterm colors: i create color schemes in TUI/CLI apps that use ANSI colors, hence inherit the theme of wezterm.

proposal:
- extend nugu to generate color schemes for gtk (and qt?)
- look for opportunities in TUI/CLI apps for better/correct ansi themes
- toggle theme state with niris: do-screen-transition
- qt: try to use gtk theme and colorscheme. if not possible, create qt colorscheme and handle theme

questions:
- does firefox benefit from custom nugu theme, or just inherit gtk theme?
- is there a freedesktop standard for system theme, or do we need gtk/qt specific way?
- does nuguland special case theme handling for itself, or since it is a qt app, it uses that mechanism?

most important apps for themeing are: niri, nuguland, firefox and wezterm. for those we need testing via screenshots.

---

workspace git/jj state in nuguland