refactor(app): reorganize App methods for better readability

- Move `refresh_objects` method inline into `update` to simplify `App` structure

src/app.rs

@@ -67,20 +67,16 @@ impl App {
 
     /// Handles the tick event of the terminal.
     pub async fn update(&mut self) {
-        self.refresh_objects().await;
-    }
-
-    /// Set running to false to quit the application.
-    pub fn quit(&mut self) {
-        self.running = false;
-    }
-
-    async fn refresh_objects(&mut self) {
         const OBJECT_UPDATE_INTERVAL: Duration = Duration::from_secs(2 * 60);
         let now = Instant::now();
         if now.duration_since(self.satellites_state.last_object_update) >= OBJECT_UPDATE_INTERVAL {
             self.satellites_state.refresh_objects().await;
             self.satellites_state.last_object_update = now;
         }
     }
+
+    /// Set running to false to quit the application.
+    pub fn quit(&mut self) {
+        self.running = false;
+    }
 }