Add tvOS app icon and top shelf images for Yattee2 brand

Generated from the existing 1024x1024 iOS icon — gradient extended
horizontally to fill the 5:3 tvOS canvas without stretching the symbol.
Top shelf images are pure blue gradients sampled from the icon.

Yattee/Assets.xcassets/Yattee2.brandassets/App Icon.imagestack/Front.imagestacklayer/Content.imageset/Contents.json

@@ -0,0 +1,18 @@
+{
+  "images" : [
+    {
+      "filename" : "tvOS-Small@1x.png",
+      "idiom" : "tv",
+      "scale" : "1x"
+    },
+    {
+      "filename" : "tvOS-Small@2x.png",
+      "idiom" : "tv",
+      "scale" : "2x"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Yattee/Assets.xcassets/Yattee2.brandassets/App Icon.imagestack/Front.imagestacklayer/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}