domain: add Media Catalog entities (Asset, Metadata, Stack, Derivative, Duplicate)

crates/domain/tests/entities/duplicate.rs

@@ -0,0 +1,19 @@
+use domain::entities::{DetectionMethod, DuplicateGroup, DuplicateStatus};
+use domain::value_objects::SystemId;
+
+#[test]
+fn exact_duplicate_group() {
+    let g = DuplicateGroup::new_exact(SystemId::new(), SystemId::new());
+    assert_eq!(g.detection_method, DetectionMethod::ExactHash);
+    assert_eq!(g.status, DuplicateStatus::Unresolved);
+    assert_eq!(g.candidates.len(), 2);
+    assert_eq!(g.candidates[0].similarity_score, 1.0);
+    assert_eq!(g.candidates[1].similarity_score, 1.0);
+}
+
+#[test]
+fn resolve_group() {
+    let mut g = DuplicateGroup::new_exact(SystemId::new(), SystemId::new());
+    g.resolve();
+    assert_eq!(g.status, DuplicateStatus::Resolved);
+}