feat: add ClassifiedAd domain entity

tests/test_classified_ad.py

@@ -0,0 +1,61 @@
+from decimal import Decimal
+from uuid import UUID, uuid4
+
+from domain.marketplace.classified_ad import ClassifiedAd
+
+
+def test_classified_ad_creation():
+    ad_id = uuid4()
+    owner_id = uuid4()
+
+    ad = ClassifiedAd(
+        id=ad_id,
+        _ownerId=owner_id,
+        title="Test Title",
+        text="Test text content",
+        _price=Decimal("99.99"),
+    )
+
+    assert ad.id == ad_id
+    assert ad._ownerId == owner_id
+    assert ad.title == "Test Title"
+    assert ad.text == "Test text content"
+    assert ad._price == Decimal("99.99")
+
+
+def test_classified_ad_is_immutable():
+    ad = ClassifiedAd(
+        id=uuid4(),
+        _ownerId=uuid4(),
+        title="Title",
+        text="Text",
+        _price=Decimal("10.00"),
+    )
+
+    try:
+        ad.title = "New Title"  # type: ignore
+        assert False, "Should have raised FrozenInstanceError"
+    except AttributeError:
+        pass
+
+
+def test_classified_ad_equality():
+    ad_id = uuid4()
+    owner_id = uuid4()
+
+    ad1 = ClassifiedAd(
+        id=ad_id,
+        _ownerId=owner_id,
+        title="Title",
+        text="Text",
+        _price=Decimal("10.00"),
+    )
+    ad2 = ClassifiedAd(
+        id=ad_id,
+        _ownerId=owner_id,
+        title="Title",
+        text="Text",
+        _price=Decimal("10.00"),
+    )
+
+    assert ad1 == ad2