feat(todo): a project laid out as a board, its columns its sections (ADR 0033, D17)

The Display's new Layout picks List or Board. The board has a column
for the tasks in no section, then one a section with its menu, each
task a card and each column ending with Add task, a last column adding
a section; grouped otherwise, a column a group. Narrower than a medium
width it pages one column at a time with dots below; from it on the
columns stand side by side. Cards drag within and between columns as
rows do (D16), every scrollable they are in scrolling at its edges.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

apps/todo/halkyon_todo_flutter/lib/l10n/app_de.arb

@@ -202,5 +202,9 @@
   "viewNothingHint": "Die Filter dieser Ansicht lassen hier jede Aufgabe aus. Unter Anzeige änderst du sie.",
   "displaySave": "Speichern",
   "displayCancel": "Abbrechen",
-  "groupNoLabel": "Ohne Label"
+  "groupNoLabel": "Ohne Label",
+  "layoutTitle": "Layout",
+  "layoutList": "Liste",
+  "layoutBoard": "Board",
+  "boardNoSection": "(Kein Abschnitt)"
 }

apps/todo/halkyon_todo_flutter/lib/l10n/app_en.arb

@@ -608,5 +608,21 @@
   "groupNoLabel": "No label",
   "@groupNoLabel": {
     "description": "A project's group of tasks without a label (ADR 0033, D17)."
+  },
+  "layoutTitle": "Layout",
+  "@layoutTitle": {
+    "description": "A project's layout in its Display, and its board's columns (ADR 0033, D17)."
+  },
+  "layoutList": "List",
+  "@layoutList": {
+    "description": "A project's layout in its Display, and its board's columns (ADR 0033, D17)."
+  },
+  "layoutBoard": "Board",
+  "@layoutBoard": {
+    "description": "A project's layout in its Display, and its board's columns (ADR 0033, D17)."
+  },
+  "boardNoSection": "(No section)",
+  "@boardNoSection": {
+    "description": "A project's layout in its Display, and its board's columns (ADR 0033, D17)."
   }
 }

apps/todo/halkyon_todo_flutter/lib/l10n/app_localizations.dart

@@ -1317,6 +1317,30 @@ abstract class AppLocalizations {
   /// In en, this message translates to:
   /// **'No label'**
   String get groupNoLabel;
+
+  /// A project's layout in its Display, and its board's columns (ADR 0033, D17).
+  ///
+  /// In en, this message translates to:
+  /// **'Layout'**
+  String get layoutTitle;
+
+  /// A project's layout in its Display, and its board's columns (ADR 0033, D17).
+  ///
+  /// In en, this message translates to:
+  /// **'List'**
+  String get layoutList;
+
+  /// A project's layout in its Display, and its board's columns (ADR 0033, D17).
+  ///
+  /// In en, this message translates to:
+  /// **'Board'**
+  String get layoutBoard;
+
+  /// A project's layout in its Display, and its board's columns (ADR 0033, D17).
+  ///
+  /// In en, this message translates to:
+  /// **'(No section)'**
+  String get boardNoSection;
 }
 
 class _AppLocalizationsDelegate

apps/todo/halkyon_todo_flutter/lib/l10n/app_localizations_de.dart

@@ -821,4 +821,16 @@ class AppLocalizationsDe extends AppLocalizations {
 
   @override
   String get groupNoLabel => 'Ohne Label';
+
+  @override
+  String get layoutTitle => 'Layout';
+
+  @override
+  String get layoutList => 'Liste';
+
+  @override
+  String get layoutBoard => 'Board';
+
+  @override
+  String get boardNoSection => '(Kein Abschnitt)';
 }

apps/todo/halkyon_todo_flutter/lib/l10n/app_localizations_en.dart

@@ -820,6 +820,18 @@ class AppLocalizationsEn extends AppLocalizations {
 
   @override
   String get groupNoLabel => 'No label';
+
+  @override
+  String get layoutTitle => 'Layout';
+
+  @override
+  String get layoutList => 'List';
+
+  @override
+  String get layoutBoard => 'Board';
+
+  @override
+  String get boardNoSection => '(No section)';
 }
 
 /// The translations for English, as used in the United Kingdom (`en_GB`).