Improved `i18n` mod to list supported languages and some other stuff
As well was added `get_default_lang` function
which will return language key based on current system language.
This function is called at the first launcher start
to update default `launcher.language` config property, so user will immediately
have proper language in initial setup window
Previously launcher wasn't downloading background picture if the style was changed from the settings. This lead to situation when the window size and components position is updated, but background is fully transparent. With this change launcher will try to download picture if default background file doesn't exist. Not that launcher won't try to update this picture and this will happen only after restart, which is not an issue, I think
Added blank first run window with welcome page. On first start launcher will create launcher folder and `.first-run` file inside if needed. If file exists - launcher will open first run window instead of the main one (to prevent further data loadings in `init` functions)
- now launcher can use `RUST_LOG` variable to filter logs
- removed "called event" logs from wine/dxvk/progress bar components
Also:
- fixed constant "remove_css_class" gtk errors
- now launcher is able to load some heavy stuff in background
so they will not freeze it during start
- patch status and latest game data is loaded in background from now
- renamed some components and their messages types for consistency
- now `General` and `Enhancements` sections are relm4 components
- this change improves code structure and should help
adding dynamic data loading on app start in future
- settings components are also not async from now because they don't need to
- classic style loads its background from "config's_tmp_path/background"
so from "launcher folder/background" by default
- icons will be changed in some future
- stdout logs got rid of rustls messages and now are pretty styled
- logs are saved into the `debug.log` file in the launcher folder
they're not filtered and contain all the messages
- toasts timeout fixed to 5 seconds
- added "save" button which will, well, not save logs
but open `debug.log` file using `xdg-open`
