Enhance apparel definitions: Introduce 'UpperUnderwear' layer and related items (Bra, SportsBra, SoftBra) to support gender-specific clothing. Update inventory and dress generation logic to accommodate new layers and ensure proper coverage. Adjust localization for new apparel terms and refine tests for underwear functionality.

src/HSchool.Content/CatalogLoader.cs

@@ -628,6 +628,14 @@ public sealed class CatalogLoader
             }
         }
 
+        foreach (var covered in thing.FullyCoversLayers)
+        {
+            if (!ApparelLayers.IsKnown(covered))
+            {
+                throw new ContentLoadException($"ThingDef '{thing.DefName}' fullyCoversLayers has unknown layer '{covered}'.");
+            }
+        }
+
         var colors = new HashSet<string>(StringComparer.Ordinal);
         foreach (var color in thing.Colors)
         {