Enhance family and roster management in school simulation by implementing support for incomplete families, ensuring proper handling of absent parents while maintaining surname consistency. Update family creation logic to account for single-parent households and revise child identification to prevent ID conflicts. Introduce seat shuffling to prevent siblings from being placed in the same class, improving the realism of student distribution. Update related tests to validate these new functionalities and ensure robustness in family and roster handling.

src/HSchool.Content/PeopleDefs.cs

@@ -21,6 +21,15 @@ public static class BodyBuilds
 {
     public const string Attribute = "Build";
 
+    /// <summary>
+    /// The two numeric attributes the build is computed from. They are named in code, so a pack
+    /// that renames or drops them is rejected at load rather than quietly producing an average
+    /// build for everybody.
+    /// </summary>
+    public const string HeightAttribute = "Height";
+
+    public const string WeightAttribute = "Weight";
+
     public const string Skinny = "Skinny";
     public const string Average = "Average";
     public const string Athletic = "Athletic";