api: Assume is_muted in subscription/update events; ignore in_home_view

See changelog for FL 139:

`GET /get-events`: When a user mutes or unmutes their subscription
  to a stream, a `subscription` update event is now sent for the
  `is_muted` property and for the deprecated `in_home_view` property
  to support clients fully migrating to use the `is_muted` property.
  Prior to this feature level, only one event was sent to clients
  with the deprecated `in_home_view` property.

Fixes-partly: zulip#1837

Author: chrisbobbe

lib/api/model/events.dart

@@ -783,7 +783,6 @@ class SubscriptionUpdateEvent extends SubscriptionEvent {
         assert(RegExp(r'^#[0-9a-f]{6}$').hasMatch(str));
         return 0xff000000 | int.parse(str.substring(1), radix: 16);
       case SubscriptionProperty.isMuted:
-      case SubscriptionProperty.inHomeView:
       case SubscriptionProperty.pinToTop:
       case SubscriptionProperty.desktopNotifications:
       case SubscriptionProperty.audibleNotifications:
@@ -820,13 +819,18 @@ enum SubscriptionProperty {
   color,
 
   isMuted,
-  inHomeView,
   pinToTop,
   desktopNotifications,
   audibleNotifications,
   pushNotifications,
   emailNotifications,
   wildcardMentionsNotify,
+
+  /// A new, unrecognized property, or a deprecated one we don't use.
+  ///
+  /// Could be `in_home_view`, deprecated in FL 139 (Server 6) but still sent
+  /// as of CZO on 2025-10-03.
+  // TODO(server-future) Remove `in_home_view` comment once it stops being sent.
   unknown;
 
   static SubscriptionProperty fromRawString(String raw) => _byRawString[raw] ?? unknown;

lib/api/model/events.g.dart

@@ -792,7 +792,6 @@ class Subscription extends ZulipStream {
 
   bool pinToTop;
   bool isMuted;
-  // final bool? inHomeView; // deprecated; ignore
 
   /// As an int that dart:ui's Color constructor will take:
   ///   <https://api.flutter.dev/flutter/dart-ui/Color/Color.html>

lib/api/model/model.dart

@@ -473,8 +473,6 @@ class ChannelStoreImpl extends HasUserStore with ChannelStore {
           case SubscriptionProperty.isMuted:
             // TODO(#1255) update [MessageListView] if affected
             subscription.isMuted                = event.value as bool;
-          case SubscriptionProperty.inHomeView:
-            subscription.isMuted                = !(event.value as bool);
           case SubscriptionProperty.pinToTop:
             subscription.pinToTop               = event.value as bool;
           case SubscriptionProperty.desktopNotifications:

lib/model/channel.dart

@@ -121,20 +121,6 @@ void main() {
         value: true));
       check(store.subscriptions[stream.streamId]!.isMuted).isTrue();
     });
-
-    test('SubscriptionProperty.inHomeView updates isMuted instead', () async {
-      final store = eg.store(initialSnapshot: eg.initialSnapshot(
-        streams: [stream],
-        subscriptions: [eg.subscription(stream, isMuted: false)],
-      ));
-      check(store.subscriptions[stream.streamId]!.isMuted).isFalse();
-
-      await store.handleEvent(SubscriptionUpdateEvent(id: 1,
-        streamId: stream.streamId,
-        property: SubscriptionProperty.inHomeView,
-        value: false));
-      check(store.subscriptions[stream.streamId]!.isMuted).isTrue();
-    });
   });
 
   group('topic visibility', () {