feat: most-popular search as default Top Results tab

Add /most-popular/get endpoint support (discovered via Burp):
- Returns mixed artists/albums/tracks ordered by popularity for a query
- New 'Top Results' tab shown first/default in the search panel
- Badge column: A (artist, blue), H (hi-res album, gold), A (album, gray), T (track, green)
- Full context menu support on all item types in the new tab
- Both most-popular and regular search fire on submit in parallel

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

rust/src/api/client.rs

@@ -384,6 +384,15 @@ impl QobuzClient {
 
     // --- Search ---
 
+    pub async fn most_popular_search(&self, query: &str, limit: u32) -> Result<serde_json::Value> {
+        let resp = self
+            .get_request("most-popular/get")
+            .query(&[("query", query), ("offset", "0"), ("limit", &limit.to_string())])
+            .send()
+            .await?;
+        Self::check_response(resp).await
+    }
+
     pub async fn search(&self, query: &str, offset: u32, limit: u32) -> Result<SearchCatalogDto> {
         let (tracks, albums, artists) = tokio::try_join!(
             self.search_tracks(query, offset, limit),