Test instrument catalog metadata

Tests/MusicAssistantCoreTests/InstrumentCatalogItemTests.swift

@@ -0,0 +1,38 @@
+import MusicAssistantCore
+import XCTest
+
+final class InstrumentCatalogItemTests: XCTestCase {
+    func testCatalogItemStoresStructuredInstrumentMetadata() {
+        let item = InstrumentCatalogItem(
+            id: "oud",
+            name: "Oud",
+            familyCategory: "Plucked strings",
+            regionOrigin: "Middle East",
+            aliases: ["Arabic lute"],
+            searchTerms: ["ud", "عود"]
+        )
+
+        XCTAssertEqual(item.id, "oud")
+        XCTAssertEqual(item.name, "Oud")
+        XCTAssertEqual(item.familyCategory, "Plucked strings")
+        XCTAssertEqual(item.regionOrigin, "Middle East")
+        XCTAssertEqual(item.aliases, ["Arabic lute"])
+        XCTAssertEqual(item.searchTerms, ["ud", "عود"])
+    }
+
+    func testCatalogItemSupportsOptionalMetadataAndRoundTripsThroughJSON() throws {
+        let item = InstrumentCatalogItem(
+            id: "synthesizer",
+            name: "Synthesizer",
+            familyCategory: "Electronic"
+        )
+
+        let data = try JSONEncoder().encode(item)
+        let decodedItem = try JSONDecoder().decode(InstrumentCatalogItem.self, from: data)
+
+        XCTAssertNil(item.regionOrigin)
+        XCTAssertEqual(item.aliases, [])
+        XCTAssertEqual(item.searchTerms, [])
+        XCTAssertEqual(decodedItem, item)
+    }
+}

docs/TASKS.md

@@ -75,7 +75,7 @@ requirement is missing and blocks implementation, record it in
 
 ## Phase 6 --- Instrument Selector & Catalog
 
--   [ ] Create structured catalog models for instrument id, name,
+-   [x] Create structured catalog models for instrument id, name,
     family/category, optional region/origin and aliases/search terms.
 -   [ ] Provide large worldwide catalog data covering Western, Middle
     Eastern, African, South Asian, East Asian, Southeast Asian, Latin