Scene/source builder with image overlays, reuse dialog, and SQLite layout persistence

Helpers/ImageCache.cs

@@ -0,0 +1,46 @@
+using System.IO;
+using System.Windows.Media.Imaging;
+using ytLive.Services;
+
+namespace ytLive.Helpers;
+
+public static class ImageCache
+{
+    private static readonly Dictionary<string, BitmapImage> Cache = new(StringComparer.OrdinalIgnoreCase);
+
+    public static BitmapImage? Get(string assetId)
+    {
+        if (string.IsNullOrWhiteSpace(assetId)) return null;
+        if (Cache.TryGetValue(assetId, out var image)) return image;
+
+        var bytes = LayoutStore.Instance?.GetAssetBytes(assetId);
+        if (bytes == null || bytes.Length == 0) return null;
+
+        var bitmap = Decode(bytes);
+        if (bitmap != null) Cache[assetId] = bitmap;
+        return bitmap;
+    }
+
+    public static void Put(string key, BitmapImage image) => Cache[key] = image;
+
+    public static BitmapImage? FromBytes(byte[] bytes)
+    {
+        try
+        {
+            using var stream = new MemoryStream(bytes, writable: false);
+            var bitmap = new BitmapImage();
+            bitmap.BeginInit();
+            bitmap.CacheOption = BitmapCacheOption.OnLoad;
+            bitmap.StreamSource = stream;
+            bitmap.EndInit();
+            bitmap.Freeze();
+            return bitmap;
+        }
+        catch
+        {
+            return null;
+        }
+    }
+
+    private static BitmapImage? Decode(byte[] bytes) => FromBytes(bytes);
+}