feat: add Control Room with containers and stacks management

- Add Control Room page with stacks sidebar and containers list
- Implement container actions (start/stop/restart) with snackbars
- Add container logs viewer dialog
- Add search/filter for both stacks and containers lists
- Add external links for Portainer and Netdata (url_launcher)
- Add VS Code launch configuration for Flutter web debugging

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/features/control_room/stacks/data/models/stack_model.dart

@@ -0,0 +1,62 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+import '../../domain/entities/stack.dart';
+
+part 'stack_model.freezed.dart';
+part 'stack_model.g.dart';
+
+/// Stack data model for API serialization.
+@freezed
+class StackModel with _$StackModel {
+  const factory StackModel({
+    required String id,
+    required String name,
+    @JsonKey(name: 'type') String? typeString,
+    @JsonKey(name: 'status') String? statusString,
+    @JsonKey(name: 'container_count') @Default(0) int containerCount,
+    @JsonKey(name: 'running_count') @Default(0) int runningCount,
+    @JsonKey(name: 'compose_file') String? composeFile,
+    String? environment,
+    @JsonKey(name: 'created_at') String? createdAt,
+    @JsonKey(name: 'updated_at') String? updatedAt,
+  }) = _StackModel;
+
+  const StackModel._();
+
+  factory StackModel.fromJson(Map<String, dynamic> json) =>
+      _$StackModelFromJson(json);
+
+  /// Converts to domain entity.
+  Stack toEntity() {
+    return Stack(
+      id: id,
+      name: name,
+      type: _parseStackType(typeString),
+      status: _parseStackStatus(statusString),
+      containerCount: containerCount,
+      runningCount: runningCount,
+      composeFile: composeFile,
+      environment: environment,
+      createdAt: createdAt != null ? DateTime.tryParse(createdAt!) : null,
+      updatedAt: updatedAt != null ? DateTime.tryParse(updatedAt!) : null,
+    );
+  }
+
+  StackType _parseStackType(String? type) {
+    return switch (type?.toLowerCase()) {
+      'compose' => StackType.compose,
+      'swarm' => StackType.swarm,
+      'kubernetes' || 'k8s' => StackType.kubernetes,
+      _ => StackType.compose,
+    };
+  }
+
+  StackStatus _parseStackStatus(String? status) {
+    return switch (status?.toLowerCase()) {
+      'active' || 'running' => StackStatus.active,
+      'inactive' || 'stopped' => StackStatus.inactive,
+      'error' => StackStatus.error,
+      _ => StackStatus.unknown,
+    };
+  }
+}