chore(repo): add lints, update freezed, json_serializable

Signed-off-by: xsahil03x <[email protected]>

packages/stream_chat_flutter/lib/src/thread_header.dart

@@ -66,7 +66,7 @@ class StreamThreadHeader extends StatelessWidget
     implements PreferredSizeWidget {
   /// Instantiate a new ThreadHeader
   const StreamThreadHeader({
-    Key? key,
+    super.key,
     required this.parent,
     this.showBackButton = true,
     this.onBackPressed,
@@ -79,8 +79,7 @@ class StreamThreadHeader extends StatelessWidget
     this.showTypingIndicator = true,
     this.backgroundColor,
     this.elevation = 1,
-  })  : preferredSize = const Size.fromHeight(kToolbarHeight),
-        super(key: key);
+  })  : preferredSize = const Size.fromHeight(kToolbarHeight);
 
   /// True if this header shows the leading back button
   final bool showBackButton;