feat: chat embeds

closes #18

lib/widgets/video_player.dart

@@ -0,0 +1,57 @@
+import 'package:chewie/chewie.dart';
+import 'package:flutter/widgets.dart';
+import 'package:video_player/video_player.dart';
+import 'package:zap_stream_flutter/imgproxy.dart';
+import 'package:zap_stream_flutter/main.dart';
+
+class VideoPlayerWidget extends StatefulWidget {
+  final String url;
+  final String? placeholder;
+  final double? aspectRatio;
+  final bool? autoPlay;
+
+  const VideoPlayerWidget({
+    super.key,
+    required this.url,
+    this.placeholder,
+    this.aspectRatio,
+    this.autoPlay,
+  });
+
+  @override
+  State<StatefulWidget> createState() => _VideoPlayerWidget();
+}
+
+class _VideoPlayerWidget extends State<VideoPlayerWidget> {
+  late final ChewieController _chewieController;
+
+  @override
+  void initState() {
+    super.initState();
+
+    final controller = VideoPlayerController.networkUrl(
+      Uri.parse(widget.url),
+      httpHeaders: Map.from({"user-agent": userAgent}),
+    );
+    _chewieController = ChewieController(
+      videoPlayerController: controller,
+      autoPlay: widget.autoPlay ?? true,
+      autoInitialize: true,
+      placeholder:
+          (widget.placeholder?.isNotEmpty ?? false)
+              ? ProxyImg(url: widget.placeholder!)
+              : null,
+    );
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    _chewieController.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Chewie(controller: _chewieController);
+  }
+}