api [nfc]: Rename streamWeeklyTraffic to channelWeeklyTraffic in Channel

Fixes parts of zulip#631

Author: Khader-1

lib/api/model/model.dart

@@ -329,7 +329,8 @@ class Channel {
   final int? canRemoveSubscribersGroup;
 
   // TODO(server-8): added in FL 199, was previously only on [Subscription] objects
-  final int? streamWeeklyTraffic;
+  @JsonKey(name: 'stream_weekly_traffic')
+  final int? channelWeeklyTraffic;
 
   static int? _readCanRemoveSubscribersGroup(Map<dynamic, dynamic> json, String key) {
     return (json[key] as int?)
@@ -349,7 +350,7 @@ class Channel {
     required this.messageRetentionDays,
     required this.channelPostPolicy,
     required this.canRemoveSubscribersGroup,
-    required this.streamWeeklyTraffic,
+    required this.channelWeeklyTraffic,
   });
 
   factory Channel.fromJson(Map<String, dynamic> json) =>
@@ -420,7 +421,7 @@ class Subscription extends Channel {
     required super.messageRetentionDays,
     required super.channelPostPolicy,
     required super.canRemoveSubscribersGroup,
-    required super.streamWeeklyTraffic,
+    required super.channelWeeklyTraffic,
     required this.desktopNotifications,
     required this.emailNotifications,
     required this.wildcardMentionsNotify,

lib/api/model/model.g.dart

@@ -162,7 +162,7 @@ Channel stream({
   int? messageRetentionDays,
   StreamPostPolicy? channelPostPolicy,
   int? canRemoveSubscribersGroup,
-  int? streamWeeklyTraffic,
+  int? channelWeeklyTraffic,
 }) {
   return Channel(
     channelId: channelId ?? 123, // TODO generate example IDs
@@ -177,7 +177,7 @@ Channel stream({
     messageRetentionDays: messageRetentionDays,
     channelPostPolicy: channelPostPolicy ?? StreamPostPolicy.any,
     canRemoveSubscribersGroup: canRemoveSubscribersGroup ?? 123,
-    streamWeeklyTraffic: streamWeeklyTraffic,
+    channelWeeklyTraffic: channelWeeklyTraffic,
   );
 }
 const _stream = stream;
@@ -210,7 +210,7 @@ Subscription subscription(
     messageRetentionDays: stream.messageRetentionDays,
     channelPostPolicy: stream.channelPostPolicy,
     canRemoveSubscribersGroup: stream.canRemoveSubscribersGroup,
-    streamWeeklyTraffic: stream.streamWeeklyTraffic,
+    channelWeeklyTraffic: stream.channelWeeklyTraffic,
     desktopNotifications: desktopNotifications ?? false,
     emailNotifications: emailNotifications ?? false,
     wildcardMentionsNotify: wildcardMentionsNotify ?? false,