add sticker and emote support

lib/models/image_data.dart

@@ -0,0 +1,11 @@
+import "package:freezed_annotation/freezed_annotation.dart";
+part "image_data.freezed.dart";
+
+@freezed
+abstract class ImageData with _$ImageData {
+  const factory ImageData({
+    required String uri,
+    required int? height,
+    required int? width,
+  }) = _ImageData;
+}