feat(todo): Today laid out as a calendar, planned from its Plan by dragging, as Todoist's desktop Today (ADR 0033, D30)

The developer asked for Todoist's desktop Today planning: a day of hours
and a Plan beside it, tasks dragged from it onto an hour. Today gets a
Display, its layout alone (List or Calendar), kept in the person's sealed
settings row as Upcoming's (`TodayView`, the payload's `today`, schema
still 1). Its Calendar is one day of `HourGrid`; *Plan: n* in its app bar
shows or hides the Plan (`PlanPanel`): Overdue with Reschedule, To plan
(today's without a time) and Time-blocked (today's with one), each
folding with its count, narrowed for the session by *All projects*'
Filter by project (a search and a box a project, a sub-project with its
parents' path). A row dropped on an hour is moved to today at that time,
its duration kept; a block dropped on the Plan loses its time; both undone
from the snack bar, through `moveTask`. From a medium width of Today's own
on the Plan stands beside the day, shown or hidden as remembered; on a
phone it is a sheet over the day's foot (the developer's choice, over the
Plan on wide windows alone and over a strip above the day), part of the
screen rather than a modal route, so that the day behind it takes the
drop, and it lowers to its heading while one of its rows is held.

Whats-New: Today's Display offers a Calendar layout: today's hours, with a Plan of what is overdue, to plan and time-blocked, whose tasks you drag onto an hour.
Whats-New-De: Die Anzeige von Heute bietet das Layout Kalender: die Stunden des Tages, mit einem Plan aus Überfälligem, Zu planen und Eingeplant, dessen Aufgaben du auf eine Stunde ziehst.

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_localizations.dart

@@ -1647,6 +1647,84 @@ abstract class AppLocalizations {
   /// In en, this message translates to:
   /// **'Show what is overdue'**
   String get overdueShow;
+
+  /// Today's app bar in its Calendar layout (ADR 0033, D30, as Todoist's): shows or hides the Plan, counting the tasks it holds.
+  ///
+  /// In en, this message translates to:
+  /// **'Plan: {count}'**
+  String planButton(int count);
+
+  /// Today's Plan beside or below its day of hours (ADR 0033, D30).
+  ///
+  /// In en, this message translates to:
+  /// **'Plan'**
+  String get planTitle;
+
+  /// Tooltip of Today's Plan button while the Plan is hidden (ADR 0033, D30).
+  ///
+  /// In en, this message translates to:
+  /// **'Show the Plan'**
+  String get planShow;
+
+  /// Tooltip of Today's Plan button and the Plan's close button while it shows (ADR 0033, D30).
+  ///
+  /// In en, this message translates to:
+  /// **'Hide the Plan'**
+  String get planHide;
+
+  /// Today's Plan (ADR 0033, D30): the group of today's tasks without a time, to be given one.
+  ///
+  /// In en, this message translates to:
+  /// **'To plan'**
+  String get planToPlan;
+
+  /// Today's Plan (ADR 0033, D30, Todoist's word): the group of today's tasks with a time.
+  ///
+  /// In en, this message translates to:
+  /// **'Time-blocked'**
+  String get planTimeBlocked;
+
+  /// Today's Plan (ADR 0033, D30) while it holds no task.
+  ///
+  /// In en, this message translates to:
+  /// **'Nothing to plan'**
+  String get planEmpty;
+
+  /// Today's Plan (ADR 0033, D30) while a block of the day is dragged over it.
+  ///
+  /// In en, this message translates to:
+  /// **'Drop here to take its time away'**
+  String get planDropHint;
+
+  /// Tooltip folding a group of Today's Plan (ADR 0033, D30).
+  ///
+  /// In en, this message translates to:
+  /// **'Hide {group}'**
+  String planGroupHide(String group);
+
+  /// Tooltip unfolding a group of Today's Plan (ADR 0033, D30).
+  ///
+  /// In en, this message translates to:
+  /// **'Show {group}'**
+  String planGroupShow(String group);
+
+  /// Today's Plan's project filter (ADR 0033, D30) while it keeps every project, and the button putting it back.
+  ///
+  /// In en, this message translates to:
+  /// **'All projects'**
+  String get planAllProjects;
+
+  /// Today's Plan's project filter (ADR 0033, D30) while it keeps several projects.
+  ///
+  /// In en, this message translates to:
+  /// **'{count, plural, =1{1 project} other{{count} projects}}'**
+  String planProjectsCount(int count);
+
+  /// Today's Plan's project filter (ADR 0033, D30): its search field's hint and its name.
+  ///
+  /// In en, this message translates to:
+  /// **'Filter by project'**
+  String get planFilterTitle;
 }
 
 class _AppLocalizationsDelegate