Enhance school day structure and decision-making for lunch breaks

- Updated `ai.md` to clarify the mechanics of hunger restoration and the importance of lunch breaks in the school schedule.
- Revised `schedule.md` to detail the new lunch break structure, allowing for separate sittings for different grade levels.
- Enhanced `Decision.cs` and `DecisionPlanner.cs` to incorporate logic for lunch breaks, ensuring that students only leave lessons during their designated lunch windows.
- Updated `DayFrameDef` and related classes to support multiple lunch breaks and validate their configurations.
- Adjusted tests to validate the new decision-making logic regarding lunch breaks and hunger management, ensuring robust functionality.
- Improved localization strings to reflect changes in the school day structure and lunch functionalities.

src/HSchool.Simulation/PresenceSystem.cs

@@ -375,6 +375,9 @@ internal static class PresenceSystem
         var bound = Duty.IsOtherStaff(person)
             ? slot.Kind != DaySlotKind.Outside
             : slot.Kind == DaySlotKind.Lesson && lessons.Any(lesson => lesson.Period == slot.Index);
+        var frame = school.Catalog!.DayFrame;
+        var lunchOpen = frame is not null
+            && SchoolDay.IsLunchWindow(frame, slot, ClassOf(school, person)?.Year);
         var state = new ActorState(
             presence.NodeId,
             presence.DestinationId,
@@ -386,7 +389,8 @@ internal static class PresenceSystem
             bound,
             duty,
             needs.Values,
-            intent);
+            intent,
+            lunchOpen);
         var decision = DecisionPlanner.Decide(
             school.Catalog!,
             school.Map!,

src/HSchool.Simulation/SchoolCreationError.cs

@@ -0,0 +1,18 @@
+namespace HSchool.Simulation;
+
+/// <summary>
+/// Why a school could not be created. Lives here rather than in the server because the checks
+/// that produce it — the name rules, the clock range — belong to the simulation.
+/// </summary>
+public enum SchoolCreationError
+{
+    None = 0,
+    LimitReached,
+    InvalidName,
+    InvalidStartDate,
+    InvalidMap,
+    UnknownMod,
+    InvalidCatalog,
+    UnknownNameSet,
+    UnknownNativeLanguage,
+}

src/HSchool.Simulation/SchoolNames.cs

@@ -0,0 +1,28 @@
+namespace HSchool.Simulation;
+
+/// <summary>
+/// The rules a school name has to pass. A name arrives from a browser, so it is trimmed and
+/// stripped before anything stores it.
+/// </summary>
+public static class SchoolNames
+{
+    /// <summary>Trims, strips control characters and enforces the length limit.</summary>
+    public static bool TryNormalize(string? name, out string normalized)
+    {
+        normalized = string.Empty;
+
+        if (string.IsNullOrWhiteSpace(name))
+        {
+            return false;
+        }
+
+        var cleaned = new string(name.Where(character => !char.IsControl(character)).ToArray()).Trim();
+        if (cleaned.Length == 0 || cleaned.Length > School.MaxNameLength)
+        {
+            return false;
+        }
+
+        normalized = cleaned;
+        return true;
+    }
+}

src/HSchool.Simulation/SchoolRegistry.cs

@@ -1,147 +0,0 @@
-namespace HSchool.Simulation;
-
-/// <summary>Why a school could not be created.</summary>
-public enum SchoolCreationError
-{
-    None = 0,
-    LimitReached,
-    InvalidName,
-    InvalidStartDate,
-    InvalidMap,
-    UnknownMod,
-    InvalidCatalog,
-    UnknownNameSet,
-    UnknownNativeLanguage,
-}
-
-/// <summary>Outcome of <see cref="SchoolRegistry.Create"/>: either the school or the reason there is none.</summary>
-public readonly record struct SchoolCreationResult(School? School, SchoolCreationError Error)
-{
-    public bool Succeeded => Error == SchoolCreationError.None && School is not null;
-
-    public static SchoolCreationResult Failed(SchoolCreationError error) => new(null, error);
-}
-
-/// <summary>
-/// In-memory set of schools plus the cap from configuration. Not thread-safe — unit tests and
-/// name/limit checks use it; the live server gives each school its own worker instead.
-/// </summary>
-public sealed class SchoolRegistry : IDisposable
-{
-    private readonly SimulationOptions _options;
-    private readonly List<School> _schools = [];
-
-    private int _nextId = 1;
-    private bool _disposed;
-
-    public SchoolRegistry(SimulationOptions options)
-    {
-        _options = options;
-        NameGenerator = new SchoolNameGenerator();
-    }
-
-    public SchoolNameGenerator NameGenerator { get; }
-
-    public int MaxSchools => _options.MaxSchools;
-
-    public int Count => _schools.Count;
-
-    public bool IsFull => _schools.Count >= _options.MaxSchools;
-
-    /// <summary>Schools in creation order — the order the menu lists them in.</summary>
-    public IReadOnlyList<School> Schools => _schools;
-
-    public School? Find(int id) => _schools.Find(school => school.Id == id);
-
-    public SchoolCreationResult Create(string name, DateTime startDate)
-    {
-        ObjectDisposedException.ThrowIf(_disposed, this);
-
-        if (IsFull)
-        {
-            return SchoolCreationResult.Failed(SchoolCreationError.LimitReached);
-        }
-
-        if (!TryNormalizeName(name, out var normalized))
-        {
-            return SchoolCreationResult.Failed(SchoolCreationError.InvalidName);
-        }
-
-        if (!GameClock.IsValidStartDate(startDate))
-        {
-            return SchoolCreationResult.Failed(SchoolCreationError.InvalidStartDate);
-        }
-
-        var school = School.Create(_nextId++, normalized, startDate);
-        _schools.Add(school);
-
-        return new SchoolCreationResult(school, SchoolCreationError.None);
-    }
-
-    public bool Delete(int id)
-    {
-        ObjectDisposedException.ThrowIf(_disposed, this);
-
-        var school = Find(id);
-        if (school is null)
-        {
-            return false;
-        }
-
-        _schools.Remove(school);
-        school.Dispose();
-        return true;
-    }
-
-    /// <summary>Advances every running school by one fixed step.</summary>
-    public void Tick()
-    {
-        ObjectDisposedException.ThrowIf(_disposed, this);
-
-        foreach (var school in _schools)
-        {
-            school.Tick(_options.FixedDeltaTime, _options.GameMinutesPerRealSecond);
-        }
-    }
-
-    /// <summary>A name the player has not used yet, for the "random" button in the creation form.</summary>
-    public string SuggestName(SchoolNameLanguage language = SchoolNameLanguage.Russian) =>
-        NameGenerator.Next(_schools.Select(school => school.Name), language);
-
-    /// <summary>Trims, strips control characters and enforces the length limit.</summary>
-    public static bool TryNormalizeName(string? name, out string normalized)
-    {
-        normalized = string.Empty;
-
-        if (string.IsNullOrWhiteSpace(name))
-        {
-            return false;
-        }
-
-        var cleaned = new string(name.Where(character => !char.IsControl(character)).ToArray()).Trim();
-        if (cleaned.Length == 0 || cleaned.Length > School.MaxNameLength)
-        {
-            return false;
-        }
-
-        normalized = cleaned;
-        return true;
-    }
-
-    public void Dispose()
-    {
-        if (_disposed)
-        {
-            return;
-        }
-
-        _disposed = true;
-
-        foreach (var school in _schools)
-        {
-            school.Dispose();
-        }
-
-        _schools.Clear();
-    }
-}