Give each school its own people seed so composition no longer follows create order.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/HSchool.Server/Game/GameCommand.cs

@@ -18,6 +18,7 @@ internal abstract record GameCommand
         MapLayout? Map,
         string? NameSetId,
         string? NativeLanguage,
+        int? Seed,
         TaskCompletionSource<SchoolCreationOutcome> Result) : GameCommand;
 
     internal sealed record DeleteSchool(int SchoolId, TaskCompletionSource<bool> Result) : GameCommand;