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

crates/domain/tests/entities/asset.rs

@@ -0,0 +1,24 @@
+use domain::entities::{Asset, AssetType, SourceReference};
+use domain::value_objects::{Checksum, SystemId};
+
+fn make_asset() -> Asset {
+    let src = SourceReference {
+        volume_id: SystemId::new(),
+        relative_path: "photos/img.jpg".to_string(),
+        checksum: Checksum::new("a".repeat(64)).unwrap(),
+    };
+    Asset::new(src, AssetType::Image, "image/jpeg", 1024, SystemId::new())
+}
+
+#[test]
+fn new_asset_is_unprocessed() {
+    let a = make_asset();
+    assert!(!a.is_processed);
+}
+
+#[test]
+fn mark_processed() {
+    let mut a = make_asset();
+    a.mark_processed();
+    assert!(a.is_processed);
+}