test(memory): cover fact upsert conflict policy and set-like values

Add tests for:
- stable upsert on same value,
- source-priority overwrite blocking/allowing,
- add/remove behavior for JSON-list (set-like) fact values.

Author: ogyrec-o

tests/test_memory_store.py

@@ -36,3 +36,119 @@ def test_memory_add_query_update_delete(tmp_path: Path) -> None:
     store.delete_memory(mem_id)
     items3 = store.query_memory(subject_type="user", subject_id="u1", limit=10)
     assert items3 == []
+
+
+def test_facts_upsert_and_conflict_policy(tmp_path: Path) -> None:
+    db = tmp_path / "memory.sqlite3"
+    store = MemoryStore(db)
+
+    fid1 = store.upsert_fact(
+        subject_type="user",
+        subject_id="u1",
+        key="preferred_name",
+        value="Alfredo",
+        confidence=0.9,
+        source="explicit",
+        evidence="запомни, меня зовут Альфредо",
+        tags=["identity"],
+        person_ref="user:u1",
+    )
+    assert fid1 > 0
+
+    # same value -> should keep same row (id stable)
+    fid2 = store.upsert_fact(
+        subject_type="user",
+        subject_id="u1",
+        key="preferred_name",
+        value="Alfredo",
+        confidence=0.95,
+        source="auto",
+        evidence="(repeat)",
+        tags=["identity", "repeat"],
+        person_ref="user:u1",
+    )
+    assert fid2 == fid1
+
+    f = store.get_fact(subject_type="user", subject_id="u1", key="preferred_name")
+    assert f is not None
+    assert f.value == "Alfredo"
+    assert f.confidence >= 0.95
+    assert "identity" in f.tags
+
+    # lower priority overwrite should be blocked
+    store.upsert_fact(
+        subject_type="user",
+        subject_id="u1",
+        key="preferred_name",
+        value="NotAlfredo",
+        confidence=0.99,
+        source="auto",
+        evidence="call me NotAlfredo",
+    )
+    f2 = store.get_fact(subject_type="user", subject_id="u1", key="preferred_name")
+    assert f2 is not None
+    assert f2.value == "Alfredo"
+
+    # higher/equal priority overwrite allowed
+    store.upsert_fact(
+        subject_type="user",
+        subject_id="u1",
+        key="preferred_name",
+        value="Alfredo The Second",
+        confidence=0.9,
+        source="explicit",
+        evidence="зови меня Alfredo The Second",
+    )
+    f3 = store.get_fact(subject_type="user", subject_id="u1", key="preferred_name")
+    assert f3 is not None
+    assert f3.value == "Alfredo The Second"
+
+
+def test_facts_set_add_remove_values(tmp_path: Path) -> None:
+    db = tmp_path / "memory.sqlite3"
+    store = MemoryStore(db)
+
+    store.add_fact_value(
+        subject_type="user",
+        subject_id="u1",
+        key="likes",
+        value="tea",
+        source="explicit",
+        evidence="запомни: я люблю чай",
+    )
+    store.add_fact_value(
+        subject_type="user",
+        subject_id="u1",
+        key="likes",
+        value="coffee",
+        source="explicit",
+        evidence="и кофе тоже",
+    )
+
+    f = store.get_fact(subject_type="user", subject_id="u1", key="likes")
+    assert f is not None
+    assert isinstance(f.value, list)
+    assert set(f.value) == {"tea", "coffee"}
+
+    store.remove_fact_value(
+        subject_type="user",
+        subject_id="u1",
+        key="likes",
+        value="tea",
+        source="explicit",
+        evidence="я больше не люблю чай",
+    )
+    f2 = store.get_fact(subject_type="user", subject_id="u1", key="likes")
+    assert f2 is not None
+    assert set(f2.value) == {"coffee"}
+
+    store.remove_fact_value(
+        subject_type="user",
+        subject_id="u1",
+        key="likes",
+        value="coffee",
+        source="explicit",
+        evidence="и кофе тоже больше не люблю",
+    )
+    f3 = store.get_fact(subject_type="user", subject_id="u1", key="likes")
+    assert f3 is None