feat(backlog): add board read models

packages/scheduler_core/lib/src/application/application_management.dart

@@ -23,6 +23,16 @@ part 'application_management/codes/owner_settings_warning_code.dart';
 part 'application_management/requests/get_backlog_request.dart';
 part 'application_management/read_models/backlog_item_read_model.dart';
 part 'application_management/read_models/backlog_query_result.dart';
+part 'application_management/read_models/backlog_board/backlog_board_column_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_board_item_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_board_query_result.dart';
+part 'application_management/read_models/backlog_board/backlog_board_summary_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_child_preview_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_distribution_entry_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_distribution_read_model.dart';
+part 'application_management/read_models/backlog_board/backlog_task_detail_read_model.dart';
+part 'application_management/read_models/backlog_board/project_option_read_model.dart';
+part 'application_management/read_models/backlog_board/suggested_slot_read_model.dart';
 part 'application_management/requests/get_project_defaults_request.dart';
 part 'application_management/read_models/project_defaults_query_result.dart';
 part 'application_management/drafts/project_profile_draft.dart';

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_board_column_read_model.dart

@@ -0,0 +1,36 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// One column in the Backlog board.
+class BacklogBoardColumnReadModel {
+  /// Creates a board column with immutable [items].
+  BacklogBoardColumnReadModel({
+    required this.bucket,
+    required this.title,
+    required this.subtitle,
+    required this.accentToken,
+    required List<BacklogBoardItemReadModel> items,
+    int? count,
+  })  : items = List<BacklogBoardItemReadModel>.unmodifiable(items),
+        count = count ?? items.length;
+
+  /// Bucket represented by this column.
+  final BacklogBoardBucket bucket;
+
+  /// Display title for the column header.
+  final String title;
+
+  /// Short display subtitle for the column header.
+  final String subtitle;
+
+  /// UI color token used by Flutter to style the column accent.
+  final String accentToken;
+
+  /// Count shown in the column header.
+  final int count;
+
+  /// Items rendered in this column.
+  final List<BacklogBoardItemReadModel> items;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_board_item_read_model.dart

@@ -0,0 +1,82 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Card-level read model for one Backlog board task.
+class BacklogBoardItemReadModel {
+  /// Creates a Backlog board item from display-ready task metadata.
+  BacklogBoardItemReadModel({
+    required this.taskId,
+    required this.title,
+    required this.projectId,
+    required this.projectName,
+    required this.projectColorToken,
+    required this.reward,
+    required this.difficulty,
+    required this.bucket,
+    required this.bucketReason,
+    required this.createdAt,
+    required this.updatedAt,
+    required List<BacklogChildPreviewReadModel> childPreview,
+    required List<String> tags,
+    this.subtitle,
+    this.durationMinutes,
+    this.priority,
+    bool? hasChildren,
+  })  : childPreview =
+            List<BacklogChildPreviewReadModel>.unmodifiable(childPreview),
+        tags = List<String>.unmodifiable(tags),
+        hasChildren = hasChildren ?? childPreview.isNotEmpty;
+
+  /// Stable task id used for selection and commands.
+  final String taskId;
+
+  /// User-facing task title.
+  final String title;
+
+  /// Optional subtitle or notes preview for card display.
+  final String? subtitle;
+
+  /// Owning project id.
+  final String projectId;
+
+  /// Display name for the owning project.
+  final String projectName;
+
+  /// UI color token for the owning project.
+  final String projectColorToken;
+
+  /// Estimated task duration in minutes, if captured.
+  final int? durationMinutes;
+
+  /// Optional task priority.
+  final PriorityLevel? priority;
+
+  /// Expected reward or payoff.
+  final RewardLevel reward;
+
+  /// Expected activation difficulty.
+  final DifficultyLevel difficulty;
+
+  /// Board bucket selected by scheduler policy.
+  final BacklogBoardBucket bucket;
+
+  /// User-facing reason for [bucket].
+  final String bucketReason;
+
+  /// Original task creation timestamp.
+  final DateTime createdAt;
+
+  /// Last task update timestamp.
+  final DateTime updatedAt;
+
+  /// Whether the task has child task metadata.
+  final bool hasChildren;
+
+  /// Preview rows for direct child tasks.
+  final List<BacklogChildPreviewReadModel> childPreview;
+
+  /// Display-ready task-local tag labels.
+  final List<String> tags;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_board_query_result.dart

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Query result for the Backlog board surface.
+class BacklogBoardQueryResult {
+  /// Creates a Backlog board result from summary, columns, and project options.
+  BacklogBoardQueryResult({
+    required this.ownerId,
+    required this.localDate,
+    required this.summary,
+    required List<BacklogBoardColumnReadModel> columns,
+    required List<ProjectOptionReadModel> projectOptions,
+  })  : columns = List<BacklogBoardColumnReadModel>.unmodifiable(columns),
+        projectOptions = List<ProjectOptionReadModel>.unmodifiable(
+          projectOptions,
+        );
+
+  /// Authorization-neutral owner scope used for the read.
+  final String ownerId;
+
+  /// Owner-local planning date used for suggested slot previews.
+  final CivilDate localDate;
+
+  /// Summary counts and planning copy derived from the same filtered item set.
+  final BacklogBoardSummaryReadModel summary;
+
+  /// Stable ordered board columns.
+  final List<BacklogBoardColumnReadModel> columns;
+
+  /// Project choices available to board and drawer controls.
+  final List<ProjectOptionReadModel> projectOptions;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_board_summary_read_model.dart

@@ -0,0 +1,35 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Summary panel read model for the Backlog board.
+class BacklogBoardSummaryReadModel {
+  /// Creates a Backlog summary from count, estimate, and distribution data.
+  const BacklogBoardSummaryReadModel({
+    required this.totalTaskCount,
+    required this.totalEstimatedMinutes,
+    required this.priorityDistribution,
+    required this.projectDistribution,
+    required this.durationDistribution,
+    required this.planningTip,
+  });
+
+  /// Total number of tasks represented by the filtered board.
+  final int totalTaskCount;
+
+  /// Sum of captured duration estimates across the filtered board.
+  final int totalEstimatedMinutes;
+
+  /// Count distribution by priority label.
+  final BacklogDistributionReadModel priorityDistribution;
+
+  /// Count distribution by project label.
+  final BacklogDistributionReadModel projectDistribution;
+
+  /// Count and percentage distribution by duration bucket.
+  final BacklogDistributionReadModel durationDistribution;
+
+  /// Display copy for the planning tip panel.
+  final String planningTip;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_child_preview_read_model.dart

@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Compact preview for a direct child task.
+class BacklogChildPreviewReadModel {
+  /// Creates a child task preview row.
+  const BacklogChildPreviewReadModel({
+    required this.taskId,
+    required this.title,
+    required this.isCompleted,
+    this.durationMinutes,
+    this.statusLabel,
+  });
+
+  /// Stable child task id.
+  final String taskId;
+
+  /// User-facing child task title.
+  final String title;
+
+  /// Estimated child task duration in minutes, if captured.
+  final int? durationMinutes;
+
+  /// Whether the child task is completed.
+  final bool isCompleted;
+
+  /// Optional display label for the child task lifecycle state.
+  final String? statusLabel;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_distribution_entry_read_model.dart

@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// One entry in a Backlog summary distribution.
+class BacklogDistributionEntryReadModel {
+  /// Creates a distribution entry.
+  const BacklogDistributionEntryReadModel({
+    required this.id,
+    required this.label,
+    required this.count,
+    required this.percentage,
+    this.colorToken,
+  });
+
+  /// Stable entry id for tests and UI keys.
+  final String id;
+
+  /// Display label for the entry.
+  final String label;
+
+  /// Number of tasks in this entry.
+  final int count;
+
+  /// Share of the parent distribution as a value from 0.0 to 1.0.
+  final double percentage;
+
+  /// Optional UI color token for the entry.
+  final String? colorToken;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_distribution_read_model.dart

@@ -0,0 +1,27 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Named distribution used by Backlog summary panels.
+class BacklogDistributionReadModel {
+  /// Creates a distribution with immutable [entries].
+  BacklogDistributionReadModel({
+    required this.title,
+    required List<BacklogDistributionEntryReadModel> entries,
+    int? totalCount,
+  })  : entries = List<BacklogDistributionEntryReadModel>.unmodifiable(
+          entries,
+        ),
+        totalCount = totalCount ??
+            entries.fold<int>(0, (sum, entry) => sum + entry.count);
+
+  /// Display title for this distribution.
+  final String title;
+
+  /// Total item count represented by [entries].
+  final int totalCount;
+
+  /// Ordered display entries.
+  final List<BacklogDistributionEntryReadModel> entries;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/backlog_task_detail_read_model.dart

@@ -0,0 +1,45 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Drawer-level read model for a selected Backlog task.
+class BacklogTaskDetailReadModel {
+  /// Creates a task detail result for the Backlog drawer.
+  BacklogTaskDetailReadModel({
+    required this.item,
+    required this.addedLabel,
+    required List<String> tags,
+    required List<ProjectOptionReadModel> projectOptions,
+    required List<SuggestedSlotReadModel> suggestedSlots,
+    this.notes,
+    this.suggestedSlotUnavailableReason,
+  })  : tags = List<String>.unmodifiable(tags),
+        projectOptions = List<ProjectOptionReadModel>.unmodifiable(
+          projectOptions,
+        ),
+        suggestedSlots = List<SuggestedSlotReadModel>.unmodifiable(
+          suggestedSlots,
+        );
+
+  /// Board card model for the selected task.
+  final BacklogBoardItemReadModel item;
+
+  /// Optional long-form notes for the drawer.
+  final String? notes;
+
+  /// Display label describing when the task was added to Backlog.
+  final String addedLabel;
+
+  /// Display-ready task-local tag labels.
+  final List<String> tags;
+
+  /// Available project choices for the selected task.
+  final List<ProjectOptionReadModel> projectOptions;
+
+  /// Non-mutating suggested schedule slots.
+  final List<SuggestedSlotReadModel> suggestedSlots;
+
+  /// Display reason when slot suggestions are unavailable.
+  final String? suggestedSlotUnavailableReason;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/project_option_read_model.dart

@@ -0,0 +1,27 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Project option exposed to Backlog board and drawer controls.
+class ProjectOptionReadModel {
+  /// Creates a project option read model.
+  const ProjectOptionReadModel({
+    required this.projectId,
+    required this.name,
+    required this.colorToken,
+    this.isArchived = false,
+  });
+
+  /// Stable project id.
+  final String projectId;
+
+  /// User-facing project name.
+  final String name;
+
+  /// UI color token for the project.
+  final String colorToken;
+
+  /// Whether this project is archived.
+  final bool isArchived;
+}

packages/scheduler_core/lib/src/application/application_management/read_models/backlog_board/suggested_slot_read_model.dart

@@ -0,0 +1,43 @@
+// SPDX-FileCopyrightText: 2026 FocusFlow contributors
+// SPDX-License-Identifier: AGPL-3.0-only
+
+part of '../../../application_management.dart';
+
+/// Preview row for a possible Backlog scheduling slot.
+class SuggestedSlotReadModel {
+  /// Creates a suggested slot preview.
+  const SuggestedSlotReadModel({
+    required this.id,
+    required this.localDateLabel,
+    required this.startText,
+    required this.endText,
+    required this.durationMinutes,
+    required this.fitLabel,
+    required this.fitSeverityToken,
+    required this.isPrimary,
+  });
+
+  /// Stable suggestion id.
+  final String id;
+
+  /// Display label for the owner-local date.
+  final String localDateLabel;
+
+  /// Display-ready start time.
+  final String startText;
+
+  /// Display-ready end time.
+  final String endText;
+
+  /// Suggested slot length in minutes.
+  final int durationMinutes;
+
+  /// Display label such as `Great Fit` or `Okay`.
+  final String fitLabel;
+
+  /// UI severity token for the fit label.
+  final String fitSeverityToken;
+
+  /// Whether this is the primary/default scheduling target.
+  final bool isPrimary;
+}

packages/scheduler_core/test/application_management_test.dart

@@ -70,6 +70,153 @@ void main() {
       );
     });
 
+    test('backlog board read models snapshot collection inputs', () {
+      final childPreviews = [
+        const BacklogChildPreviewReadModel(
+          taskId: 'child-1',
+          title: 'Gather statements',
+          isCompleted: false,
+          durationMinutes: 15,
+          statusLabel: 'Backlog',
+        ),
+      ];
+      final itemTags = ['finance'];
+      final item = BacklogBoardItemReadModel(
+        taskId: 'review-budget',
+        title: 'Review Q3 budget',
+        subtitle: 'Check the draft before planning.',
+        projectId: 'work',
+        projectName: 'Work',
+        projectColorToken: 'project-work',
+        durationMinutes: 60,
+        priority: PriorityLevel.high,
+        reward: RewardLevel.medium,
+        difficulty: DifficultyLevel.easy,
+        bucket: BacklogBoardBucket.needTimeBlock,
+        bucketReason: 'Needs a focused time block.',
+        createdAt: now,
+        updatedAt: now,
+        childPreview: childPreviews,
+        tags: itemTags,
+      );
+
+      childPreviews.clear();
+      itemTags.add('late');
+
+      expect(item.childPreview, hasLength(1));
+      expect(item.tags, ['finance']);
+      expect(() => item.tags.add('new'), throwsUnsupportedError);
+
+      final items = [item];
+      final column = BacklogBoardColumnReadModel(
+        bucket: BacklogBoardBucket.needTimeBlock,
+        title: 'Need Time Block',
+        subtitle: 'Plan deliberately.',
+        accentToken: 'backlog-time-block',
+        items: items,
+      );
+      items.clear();
+
+      expect(column.count, 1);
+      expect(column.items, [item]);
+      expect(() => column.items.clear(), throwsUnsupportedError);
+
+      final entries = [
+        const BacklogDistributionEntryReadModel(
+          id: 'high',
+          label: 'High',
+          count: 2,
+          percentage: 1,
+          colorToken: 'priority-high',
+        ),
+      ];
+      final priorityDistribution = BacklogDistributionReadModel(
+        title: 'Priority',
+        entries: entries,
+      );
+      entries.clear();
+
+      expect(priorityDistribution.totalCount, 2);
+      expect(priorityDistribution.entries, hasLength(1));
+      expect(
+        () => priorityDistribution.entries.clear(),
+        throwsUnsupportedError,
+      );
+
+      final projects = [
+        const ProjectOptionReadModel(
+          projectId: 'work',
+          name: 'Work',
+          colorToken: 'project-work',
+        ),
+      ];
+      final summary = BacklogBoardSummaryReadModel(
+        totalTaskCount: 1,
+        totalEstimatedMinutes: 60,
+        priorityDistribution: priorityDistribution,
+        projectDistribution: BacklogDistributionReadModel(
+          title: 'Project',
+          entries: const [
+            BacklogDistributionEntryReadModel(
+              id: 'work',
+              label: 'Work',
+              count: 1,
+              percentage: 1,
+              colorToken: 'project-work',
+            ),
+          ],
+        ),
+        durationDistribution: BacklogDistributionReadModel(
+          title: 'Duration',
+          entries: const [
+            BacklogDistributionEntryReadModel(
+              id: '30-60',
+              label: '30-60',
+              count: 1,
+              percentage: 1,
+            ),
+          ],
+        ),
+        planningTip: 'Pick one focused task before adding more.',
+      );
+      final result = BacklogBoardQueryResult(
+        ownerId: 'owner-1',
+        localDate: CivilDate(2026, 6, 25),
+        summary: summary,
+        columns: [column],
+        projectOptions: projects,
+      );
+      projects.clear();
+
+      expect(result.columns, [column]);
+      expect(result.projectOptions, hasLength(1));
+      expect(() => result.projectOptions.clear(), throwsUnsupportedError);
+
+      final detail = BacklogTaskDetailReadModel(
+        item: item,
+        addedLabel: 'Added today',
+        tags: const ['finance'],
+        projectOptions: result.projectOptions,
+        suggestedSlots: const [
+          SuggestedSlotReadModel(
+            id: 'today-1',
+            localDateLabel: 'Today',
+            startText: '2:00 PM',
+            endText: '3:00 PM',
+            durationMinutes: 60,
+            fitLabel: 'Great Fit',
+            fitSeverityToken: 'fit-great',
+            isPrimary: true,
+          ),
+        ],
+        notes: 'Review budget categories before scheduling.',
+      );
+
+      expect(detail.tags, ['finance']);
+      expect(detail.suggestedSlots.single.fitLabel, 'Great Fit');
+      expect(() => detail.suggestedSlots.clear(), throwsUnsupportedError);
+    });
+
     test('keeps configured project defaults separate from learned suggestions',
         () async {
       final project = ProjectProfile(