Added playing song view. Adding styling to playing song. Fixed caching cancellation issue.

Harmonia.Core/Caching/Cache.cs

@@ -32,30 +32,39 @@ public abstract class Cache<TKey, TValue> : ICache<TKey, TValue> where TKey : no
 
         SemaphoreSlim lockObject = _locks.GetOrAdd(actualKey, (key) => new SemaphoreSlim(1, 1));
 
+        bool throttlerAcquired = false;
+        bool lockAcquired = false;
+
         try
         {
             await _throttler.WaitAsync(cancellationToken);
+            throttlerAcquired = true;
 
             if (cancellationToken.IsCancellationRequested)
                 return default;
 
             await lockObject.WaitAsync(cancellationToken);
+            lockAcquired = true;
 
             if (cancellationToken.IsCancellationRequested)
                 return default;
 
             return TryGetValue(actualKey) ?? await FetchAsync2(key, cancellationToken);
         }
+        catch (OperationCanceledException)
+        {
+            return default;
+        }
         finally
         {
-            lockObject.Release();
+            if (lockAcquired)
+                lockObject.Release();
 
             _locks.TryRemove(lockObject, out _);
 
-            _throttler.Release();
+            if (throttlerAcquired)
+                _throttler.Release();
         }
-
-        //return TryGetValue(actualKey) ?? Refresh(key);
     }
 
     private async Task<TValue?> FetchAsync2(TKey key, CancellationToken cancellationToken)