Initial commit: COPILOT D6 Flutter keyboard controller

Flutter web app replacing legacy WPF CCTV surveillance keyboard controller.
Includes wall overview, section view with monitor grid, camera input,
PTZ control, alarm/lock/sequence BLoCs, and legacy-matching UI styling.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

copilot_keyboard/lib/domain/entities/sequence.dart

@@ -0,0 +1,72 @@
+/// Sequence definition loaded from the coordinator.
+class SequenceDefinition {
+  final int id;
+  final String name;
+  final int categoryId;
+  final List<int> cameras;
+  final int intervalSeconds;
+
+  const SequenceDefinition({
+    required this.id,
+    required this.name,
+    required this.categoryId,
+    required this.cameras,
+    required this.intervalSeconds,
+  });
+
+  factory SequenceDefinition.fromJson(Map<String, dynamic> json) {
+    return SequenceDefinition(
+      id: json['id'] as int? ?? json['Id'] as int? ?? 0,
+      name: json['name'] as String? ?? json['Name'] as String? ?? '',
+      categoryId:
+          json['categoryId'] as int? ?? json['CategoryId'] as int? ?? 0,
+      cameras: (json['cameras'] as List<dynamic>? ??
+              json['Cameras'] as List<dynamic>? ??
+              [])
+          .cast<int>(),
+      intervalSeconds: json['intervalSeconds'] as int? ??
+          json['IntervalSeconds'] as int? ??
+          5,
+    );
+  }
+}
+
+/// Sequence category for grouping sequences.
+class SequenceCategory {
+  final int id;
+  final String name;
+
+  const SequenceCategory({required this.id, required this.name});
+
+  factory SequenceCategory.fromJson(Map<String, dynamic> json) {
+    return SequenceCategory(
+      id: json['id'] as int? ?? json['Id'] as int? ?? 0,
+      name: json['name'] as String? ?? json['Name'] as String? ?? '',
+    );
+  }
+}
+
+/// A sequence currently running on a viewer.
+class RunningSequence {
+  final int viewerId;
+  final int sequenceId;
+  final DateTime startedAt;
+
+  const RunningSequence({
+    required this.viewerId,
+    required this.sequenceId,
+    required this.startedAt,
+  });
+
+  factory RunningSequence.fromJson(Map<String, dynamic> json) {
+    return RunningSequence(
+      viewerId: json['viewerId'] as int? ?? json['ViewerId'] as int? ?? 0,
+      sequenceId:
+          json['sequenceId'] as int? ?? json['SequenceId'] as int? ?? 0,
+      startedAt: DateTime.tryParse(json['startedAt'] as String? ??
+              json['StartedAt'] as String? ??
+              '') ??
+          DateTime.now(),
+    );
+  }
+}