Add a delay action

DelayAction waits a number of milliseconds before the next action runs.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VtH72Dg3rGsqwaEe62Sha4

Author: claude

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## Unreleased
 
+- `DelayAction` (`ActionType.delay`): waits `milliseconds` before the next
+  action runs.
 - `CanvasProperties.signInRedirectId`: a screen that needs a signed-in user
   sends signed-out users to that canvas (`requiresSignIn`).
 - `ListViewNode.statusVariable` and `GridViewNode.statusVariable`: a text

lib/src/api/models/action/action.dart

@@ -55,7 +55,10 @@ enum ActionType {
   showToast,
 
   /// Ask the user to confirm, then branch on their answer.
-  confirm;
+  confirm,
+
+  /// Wait before running the next action.
+  delay;
 
   /// Displayable string representation of the [ActionType].
   String get prettify {
@@ -96,6 +99,8 @@ enum ActionType {
         return 'Show Toast';
       case ActionType.confirm:
         return 'Confirm Dialog';
+      case ActionType.delay:
+        return 'Delay';
     }
   }
 }
@@ -181,6 +186,8 @@ abstract class ActionModel with SerializableMixin {
         return ShowToastAction.fromJson(json);
       case ActionType.confirm:
         return ConfirmAction.fromJson(json);
+      case ActionType.delay:
+        return DelayAction.fromJson(json);
     }
   }
 

lib/src/api/models/action/api_call_action.g.dart

@@ -0,0 +1,38 @@
+import 'package:equatable/equatable.dart';
+import 'package:json_annotation/json_annotation.dart';
+
+import '../../mixins.dart';
+import '../models.dart';
+
+part 'delay_action.g.dart';
+
+/// Waits before the next action runs, e.g. to let a toast show before
+/// navigating away.
+@JsonSerializable()
+class DelayAction extends ActionModel with Equatable, SerializableMixin {
+  /// How long to wait, in milliseconds.
+  final int milliseconds;
+
+  /// Creates a [DelayAction].
+  DelayAction({this.milliseconds = 500, super.nonBlocking, super.enabled})
+    : super(type: ActionType.delay);
+
+  /// Duplicates this action with the given values replaced.
+  DelayAction copyWith({int? milliseconds}) => DelayAction(
+    milliseconds: milliseconds ?? this.milliseconds,
+    nonBlocking: nonBlocking,
+    enabled: enabled,
+  );
+
+  @override
+  List<Object?> get props => [milliseconds];
+
+  /// Creates an instance from a JSON object.
+  factory DelayAction.fromJson(Map json) => _$DelayActionFromJson(json);
+
+  @override
+  Map toJson() => _$DelayActionOmitDefaults(this, _$DelayActionToJson(this));
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitDelayAction(this);
+}