Refactored the UI module and the handlers module to do a more chain-of-responsibility method to manage the UI's and handlers for different key events. Also, initial work for indexer settings as well

src/ui/radarr_ui/indexers/indexer_settings_ui.rs

@@ -0,0 +1,26 @@
+use tui::backend::Backend;
+use tui::layout::Rect;
+use tui::Frame;
+
+use crate::app::radarr::INDEXER_SETTINGS_BLOCKS;
+use crate::app::App;
+use crate::models::Route;
+use crate::ui::DrawUi;
+
+#[cfg(test)]
+#[path = "indexer_settings_ui_tests.rs"]
+mod indexer_settings_ui_tests;
+
+pub(super) struct IndexerSettingsUi {}
+
+impl DrawUi for IndexerSettingsUi {
+  fn accepts(route: Route) -> bool {
+    if let Route::Radarr(active_radarr_block, _) = route {
+      return INDEXER_SETTINGS_BLOCKS.contains(&active_radarr_block);
+    }
+
+    false
+  }
+
+  fn draw<B: Backend>(_f: &mut Frame<'_, B>, _app: &mut App<'_>, _content_rect: Rect) {}
+}