Update wire protocol to version 6 and enhance timetable functionality

- Bumped the wire protocol version to 6, reflecting changes in the communication structure.
- Expanded the timetable API with new endpoints for fetching and managing lesson schedules, including `GET /api/schools/{id}/timetable` and `POST /api/schools/{id}/timetable/pin`.
- Updated the protocol documentation to include detailed descriptions of the new timetable features and message structures.
- Enhanced the client-side implementation to support the new timetable functionalities, including lesson pinning and unpinning.
- Revised server-side logic to handle timetable operations and ensure proper integration with existing school management features.
- Added tests to validate the new timetable functionalities and ensure robustness in handling lesson data.

src/HSchool.Server/Game/GameLoopService.cs

@@ -1,6 +1,7 @@
 using HSchool.Content;
 using HSchool.People;
 using HSchool.Protocol;
+using HSchool.Schedule;
 using HSchool.Server.Api;
 using HSchool.Server.Net;
 using HSchool.Simulation;
@@ -64,7 +65,12 @@ internal sealed class GameLoopService(
         {
             if (worker.Id == schoolId)
             {
-                return new PublishedSchoolPeople(worker.Snapshot, worker.RosterSnapshot, worker.ApplicantSnapshot, worker.CatalogSnapshot);
+                return new PublishedSchoolPeople(
+                    worker.Snapshot,
+                    worker.RosterSnapshot,
+                    worker.ApplicantSnapshot,
+                    worker.CatalogSnapshot,
+                    worker.TimetableSnapshot);
             }
         }
 
@@ -192,6 +198,20 @@ internal sealed class GameLoopService(
                     new WorkerCommand.UnassignSubject(unassign.PersonId, unassign.Subject, unassign.Result),
                     unassign.Result);
                 break;
+
+            case GameCommand.PinLesson pin:
+                HandleTimetable(
+                    pin.SchoolId,
+                    new WorkerCommand.PinLesson(pin.ClassId, pin.Subject, pin.RoomId, pin.Day, pin.Period, pin.Result),
+                    pin.Result);
+                break;
+
+            case GameCommand.UnpinLesson unpin:
+                HandleTimetable(
+                    unpin.SchoolId,
+                    new WorkerCommand.UnpinLesson(unpin.ClassId, unpin.Subject, unpin.Day, unpin.Period, unpin.Result),
+                    unpin.Result);
+                break;
         }
     }
 
@@ -212,6 +232,14 @@ internal sealed class GameLoopService(
         }
     }
 
+    private void HandleTimetable(int schoolId, WorkerCommand command, TaskCompletionSource<TimetableOutcome> result)
+    {
+        if (!_workers.TryGetValue(schoolId, out var worker) || !worker.Post(command))
+        {
+            result.TrySetResult(TimetableOutcome.Fail(TimetableError.UnknownSchool));
+        }
+    }
+
     /// <summary>
     /// A school's thread died. Drop it from the table so the menu stops drawing a card whose clock
     /// never moves again, and tell anybody watching it to go back to the menu. The save file stays
@@ -610,4 +638,9 @@ internal sealed class GameLoopService(
     }
 }
 
-internal sealed record PublishedSchoolPeople(SchoolState School, Roster? Roster, ApplicantPool? Applicants, DefCatalog? Catalog);
+internal sealed record PublishedSchoolPeople(
+    SchoolState School,
+    Roster? Roster,
+    ApplicantPool? Applicants,
+    DefCatalog? Catalog,
+    Timetable? Timetable);