Add trait dependency documentation and architecture diagrams

Co-authored-by: jbtronics <5410681+jbtronics@users.noreply.github.com>

src/Entity/Base/AttachmentsTrait.php

@@ -29,6 +29,11 @@ use Symfony\Component\Serializer\Annotation\Groups;
 
 /**
  * Trait providing attachments functionality.
+ *
+ * Requirements:
+ * - Class using this trait should have $id property (e.g., via DBElementTrait)
+ * - Class may optionally have $master_picture_attachment property (via MasterAttachmentTrait)
+ * - Class should implement HasAttachmentsInterface
  */
 trait AttachmentsTrait
 {

src/Entity/Base/StructuralElementTrait.php

@@ -34,6 +34,11 @@ use function count;
 
 /**
  * Trait for structural/hierarchical elements forming a tree structure.
+ *
+ * Requirements:
+ * - Class using this trait must have getName() method (e.g., via NamedElementTrait)
+ * - Class using this trait must have getID() method (e.g., via DBElementTrait)
+ * - Class should implement StructuralElementInterface
  */
 trait StructuralElementTrait
 {