feat(suggestions): major UX overhaul with popular tracks fallback

Backend:
- Add get_artist_tracks command for fetching artist's popular tracks

Frontend:
- Fallback to artist's popular tracks when tracks_appears_on is sparse
- Remove card hover movement, only image moves up on hover
- Add hover overlay with (add to queue) (play) (play next) buttons
- Use playlist.svg icon for playlist cards and glyph
- Radio glyph shown by default, replaced by action buttons on hover
- Fix icon sizes: QBZ (22px) vs Qobuz (18px) for visual balance
- Track playlist.svg asset

src-tauri/src/commands/search.rs

@@ -2,7 +2,7 @@
 
 use tauri::State;
 
-use crate::api::{Album, Artist, ArtistAlbums, LabelDetail, SearchResultsPage, Track};
+use crate::api::{Album, Artist, ArtistAlbums, LabelDetail, SearchResultsPage, Track, TracksContainer};
 use crate::api_cache::ApiCacheState;
 use crate::AppState;
 use serde::{Deserialize, Serialize};
@@ -222,6 +222,28 @@ pub async fn get_artist_detail(
         .map_err(|e| e.to_string())
 }
 
+/// Get artist's popular/top tracks
+#[tauri::command]
+pub async fn get_artist_tracks(
+    artist_id: u64,
+    limit: Option<u32>,
+    offset: Option<u32>,
+    state: State<'_, AppState>,
+) -> Result<TracksContainer, String> {
+    log::info!(
+        "Command: get_artist_tracks {} limit={:?} offset={:?}",
+        artist_id,
+        limit,
+        offset
+    );
+
+    let client = state.client.lock().await;
+    client
+        .get_artist_tracks(artist_id, limit.unwrap_or(50), offset.unwrap_or(0))
+        .await
+        .map_err(|e| e.to_string())
+}
+
 /// Get artist albums with pagination (for load more)
 #[tauri::command]
 pub async fn get_artist_albums(

src-tauri/src/lib.rs

@@ -478,6 +478,7 @@ pub fn run() {
             commands::get_track,
             commands::get_artist,
             commands::get_artist_detail,
+            commands::get_artist_tracks,
             commands::get_artist_albums,
             commands::get_similar_artists,
             commands::get_label,