Queue close from windows animation callback instead of calling it directly; fix null pointer (double cleanup) in certain scenarios (#649)

* update the config.json to be in sync with latest swaync(5) page

Fixes: #641

* set cssPriority to 'user'

The swaync(5) manpage must be changed as well, since it currently says "application" is the default value.

In waybar formatting, adding "{}" only works when adding it before the icon. It breaks when adding it after the icon. This change fixes the snippet in our README, so that if someone copies our snippet, it will be easier to make changes.

* Search by process name when icon is missing

* fix formatting

* fix linting errors

I forgot to set the initial visible state to false, so it would be
visible, even with only one player active

* feat: Choose outputs by name

* Match the full monitor name + serial number like sway does

* Updated documentation

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Co-authored-by: Erik Reider <35975961+ErikReider@users.noreply.github.com>

Caused by "app.config_reload" in the control center. Changing a value,
reloading, and then chaning it again and reloading -> segfault

* Moved control center notifications into its own widget + vexpand config option

* Fixed cc max size not being respected

All the widgets now have the same padding and margins

Makes it easier to override variables like border radius without
recompiling the original SCSS

* Always use the default GTK theme to allow for a more consistent theming experience

* Default to USER CSS priority