Add automatic generation of favourite buttons

favourite buttons are based on how often a good i added to list
finished implementing setting category
made number of days until button an environment variable

rebase on main and fix

ran cargo fmt

gui/src/config.rs

@@ -18,6 +18,8 @@ pub use fs::*;
 
 #[cfg(target_os = "linux")]
 mod fs {
+    use crate::runtime::spawn;
+
     use super::Config;
     use anyhow::{Context, Ok};
 
@@ -33,7 +35,7 @@ mod fs {
             .place_config_file(CONFIG_FILE_NAME)
             .context("unable to create config directory")?;
 
-        tokio::spawn(async {
+        spawn(async {
             let res = tokio::fs::write(path, conf)
                 .await
                 .context("unable to write config file");