feat: add conversation_summaries DB helpers

Add upsert_conversation_summary() and search_similar_conversation_summaries()
functions to manage conversation summaries with vector embeddings. These helpers
support cross-chat memory retrieval and background summarization tasks.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019iZMEPk2Kt1UC96Lo9bC5w

Claude outputs/main.py

@@ -302,6 +302,32 @@ async def get_all_memory_facts() -> list:
     )
 
 
+async def upsert_conversation_summary(conversation_id: int, summary: str, embedding: list):
+    await db_query(
+        """
+        INSERT INTO conversation_summaries (conversation_id, summary, embedding)
+        VALUES (%s, %s, %s::vector)
+        ON CONFLICT (conversation_id) DO UPDATE
+        SET summary = EXCLUDED.summary, embedding = EXCLUDED.embedding, updated_at = CURRENT_TIMESTAMP
+        """,
+        (conversation_id, summary, _vector_literal(embedding)),
+    )
+
+
+async def search_similar_conversation_summaries(query_embedding: list, exclude_conversation_id: int, limit: int = 3) -> list:
+    return await db_query(
+        """
+        SELECT conversation_id, summary, embedding <=> %s::vector AS distance
+        FROM conversation_summaries
+        WHERE conversation_id != %s
+        ORDER BY distance ASC
+        LIMIT %s
+        """,
+        (_vector_literal(query_embedding), exclude_conversation_id, limit),
+        fetch="all",
+    )
+
+
 def _caldav_calendar():
     dav_root = NEXTCLOUD_CALDAV_URL.split("/calendars/")[0] + "/"
     client = caldav.DAVClient(url=dav_root, username=NEXTCLOUD_USER, password=NEXTCLOUD_APP_PASSWORD)

Claude outputs/tests/test_memory.py

@@ -59,3 +59,26 @@ async def test_get_all_memory_facts_returns_rows():
         result = await main.get_all_memory_facts()
 
     assert result == rows
+
+
+@pytest.mark.asyncio
+async def test_upsert_conversation_summary_inserts_with_vector_literal():
+    with patch.object(main, "db_query", new=AsyncMock(return_value=None)) as mock_query:
+        await main.upsert_conversation_summary(5, "Kurze Zusammenfassung", [0.1, 0.2])
+
+    args, kwargs = mock_query.call_args
+    assert "INSERT INTO conversation_summaries" in args[0]
+    assert "ON CONFLICT (conversation_id) DO UPDATE" in args[0]
+    assert args[1] == (5, "Kurze Zusammenfassung", "[0.1,0.2]")
+
+
+@pytest.mark.asyncio
+async def test_search_similar_conversation_summaries_excludes_current_conversation():
+    rows = [{"conversation_id": 3, "summary": "Ueber Kalender", "distance": 0.1}]
+    with patch.object(main, "db_query", new=AsyncMock(return_value=rows)) as mock_query:
+        result = await main.search_similar_conversation_summaries([0.1, 0.2], exclude_conversation_id=9, limit=3)
+
+    assert result == rows
+    args, kwargs = mock_query.call_args
+    assert "conversation_id != %s" in args[0]
+    assert args[1] == ("[0.1,0.2]", 9, 3)