Refactor initial 'Scanning Disks' popup

Starting that in app.rs makes more sense

core/src/components/popup.rs

@@ -43,10 +43,7 @@ pub struct Popup {
 
 impl Popup {
     pub fn new() -> Self {
-        Self {
-            popup_text: String::from("Scanning Disks..."),
-            ..Default::default()
-        }
+        Self::default()
     }
 }
 

deja_vu/src/app.rs

@@ -269,6 +269,10 @@ impl App {
         }
 
         let action_tx = self.action_tx.clone();
+        action_tx.send(Action::DisplayPopup(
+            popup::Type::Info,
+            String::from("Scanning Disks..."),
+        ))?;
         loop {
             self.handle_events(&mut tui).await?;
             self.handle_actions(&mut tui)?;