Remove flutter chat (#26)

Had to squash merge manually as Forgejo was erroring

lib/models/info/video.dart

@@ -0,0 +1,19 @@
+import "package:freezed_annotation/freezed_annotation.dart";
+import "package:nexus/models/ms_duration.dart";
+part "video.freezed.dart";
+part "video.g.dart";
+
+@freezed
+abstract class VideoInfo with _$VideoInfo {
+  /// Information for images, [size] is in bytes.
+  const factory VideoInfo({
+    @JsonKey(name: "h") int? height,
+    @JsonKey(name: "w") int? width,
+    @JsonKey(name: "mimetype") String? mimeType,
+    @MSDuration() Duration? duration,
+    int? size,
+  }) = _VideoInfo;
+
+  factory VideoInfo.fromJson(Map<String, Object?> json) =>
+      _$VideoInfoFromJson(json);
+}