feat(slint): favorites load error + retry state

navigate_favorites stores the load error in FavoritesState.load-error
(cleared on each load attempt); the view shows a "Couldn't load
favorites" + detail + Retry block when set, and the tracks/albums tabs
are gated so the error replaces them instead of showing alongside an
empty state. Retry re-navigates the current tab.

cc

crates/qbz-slint/src/favorites.rs

@@ -717,7 +717,9 @@ pub fn selected_ids(window: &AppWindow) -> Vec<String> {
 }
 
 pub fn reset_loading(window: &AppWindow) {
-    window.global::<FavoritesState>().set_loading(true);
+    let state = window.global::<FavoritesState>();
+    state.set_loading(true);
+    state.set_load_error("".into());
 }
 
 /// Artwork jobs for the freshly loaded tab.

crates/qbz-slint/src/main.rs

@@ -791,8 +791,11 @@ fn navigate_favorites(
             }
             Err(e) => {
                 log::error!("[qbz-slint] favorites load failed: {e}");
-                let _ = weak.upgrade_in_event_loop(|w| {
-                    w.global::<FavoritesState>().set_loading(false);
+                let msg = e.to_string();
+                let _ = weak.upgrade_in_event_loop(move |w| {
+                    let st = w.global::<FavoritesState>();
+                    st.set_loading(false);
+                    st.set_load_error(msg.into());
                 });
             }
         }
@@ -4385,6 +4388,30 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                 });
             });
     }
+    {
+        // Retry loading the current favorites tab after a load error.
+        let runtime = app_runtime.clone();
+        let weak = window.as_weak();
+        let handle = tokio_rt.handle().clone();
+        let image_cache = image_cache.clone();
+        window
+            .global::<FavoritesActions>()
+            .on_retry_load(move || {
+                if let Some(w) = weak.upgrade() {
+                    let tab_id = w.global::<FavoritesState>().get_active_tab().to_string();
+                    if let Some(tab) = favorites::FavTab::from_tab_id(&tab_id) {
+                        navigate_favorites(
+                            runtime.clone(),
+                            weak.clone(),
+                            &handle,
+                            image_cache.clone(),
+                            tab,
+                            &tab_id,
+                        );
+                    }
+                }
+            });
+    }
     {
         // Local search over the loaded favorite tracks (title / artist /
         // album), re-deriving the rendered list.

crates/qbz-slint/ui/favorites/FavoritesView.slint

@@ -390,8 +390,52 @@ export component FavoritesView inherits Rectangle {
                 LoadingSpinner { size: 36px; }
             }
 
+            // Load error + retry.
+            if !FavoritesState.loading && FavoritesState.load-error != "": VerticalLayout {
+                alignment: center;
+                spacing: 10px;
+                Rectangle { height: 24px; }
+                Text {
+                    text: @tr("Couldn't load favorites.");
+                    color: Theme.text-primary;
+                    font-size: Typography.body;
+                    font-weight: Typography.semibold;
+                    horizontal-alignment: center;
+                }
+                Text {
+                    text: FavoritesState.load-error;
+                    color: Theme.text-muted;
+                    font-size: Typography.legal;
+                    horizontal-alignment: center;
+                }
+                HorizontalLayout {
+                    alignment: center;
+                    Rectangle {
+                        width: retry-label.preferred-width + 28px;
+                        height: 32px;
+                        border-radius: 6px;
+                        background: retry-ta.has-hover ? Theme.surface-hover : Theme.surface-elevated;
+                        border-width: 1px;
+                        border-color: Theme.border-subtle;
+                        retry-label := Text {
+                            text: @tr("Retry");
+                            color: Theme.text-primary;
+                            font-size: Typography.legal;
+                            x: (parent.width - self.width) / 2;
+                            y: (parent.height - self.height) / 2;
+                        }
+                        retry-ta := TouchArea {
+                            mouse-cursor: pointer;
+                            clicked => {
+                                FavoritesActions.retry-load();
+                            }
+                        }
+                    }
+                }
+            }
+
             // --- Tracks tab --------------------------------------------
-            if !FavoritesState.loading
+            if !FavoritesState.loading && FavoritesState.load-error == ""
                 && FavoritesState.active-tab == "tracks": VerticalLayout {
                 spacing: 0px;
                 // Toolbar — results count (left) + expandable search (right).
@@ -499,7 +543,7 @@ export component FavoritesView inherits Rectangle {
             }
 
             // --- Albums tab --------------------------------------------
-            if !FavoritesState.loading
+            if !FavoritesState.loading && FavoritesState.load-error == ""
                 && FavoritesState.active-tab == "albums": VerticalLayout {
                 spacing: 0px;
                 // Toolbar — count (left) + grid/list segmented toggle (right).

crates/qbz-slint/ui/state.slint

@@ -1478,6 +1478,7 @@ export global FavoritesState {
     in property <int> playlists-total: 0;
     in property <int> labels-total: 0;
     in property <bool> loading: false;
+    in property <string> load-error: ""; // non-empty -> show error + retry
 }
 
 export global FavoritesActions {
@@ -1503,6 +1504,7 @@ export global FavoritesActions {
     callback albums-shuffle();
     callback unfavorite-track(string /* track id */);
     callback unfavorite-album(string /* album id */);
+    callback retry-load();
 }
 
 // A Qobuz mix detail page (DailyQ / WeeklyQ / FavQ / TopQ), opened