feat: Initial support for custom user-defined themes

src/app/app_tests.rs

@@ -31,6 +31,7 @@ mod tests {
     };
     let sonarr_config_2 = ServarrConfig::default();
     let config = AppConfig {
+      theme: None,
       radarr: Some(vec![radarr_config_1.clone(), radarr_config_2.clone()]),
       sonarr: Some(vec![sonarr_config_1.clone(), sonarr_config_2.clone()]),
     };

src/app/mod.rs

@@ -270,6 +270,7 @@ pub struct Data<'a> {
 
 #[derive(Debug, Deserialize, Serialize, Default, Clone)]
 pub struct AppConfig {
+  pub theme: Option<String>,
   pub radarr: Option<Vec<ServarrConfig>>,
   pub sonarr: Option<Vec<ServarrConfig>>,
 }