Enable phase-3 task memory filtering and add coverage

backend/test/test_task_memory_service.py

@@ -0,0 +1,101 @@
+from datetime import datetime
+from types import SimpleNamespace
+from unittest.mock import AsyncMock
+
+import pytest
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from models.daily_workflow_models import TaskHistory
+from models.enhanced_strategy_models import Base
+from services.task_memory_service import TaskMemoryService
+
+
+@pytest.fixture
+def db_session():
+    engine = create_engine("sqlite:///:memory:")
+    Base.metadata.create_all(engine, tables=[TaskHistory.__table__])
+    SessionLocal = sessionmaker(bind=engine)
+    session = SessionLocal()
+    try:
+        yield session
+    finally:
+        session.close()
+
+
+@pytest.mark.asyncio
+async def test_filter_redundant_proposals_suppresses_exact_hash_duplicates(db_session):
+    service = TaskMemoryService(user_id="user-1", db=db_session)
+    service.intelligence = SimpleNamespace(search=AsyncMock(return_value=[]))
+
+    title = "Create LinkedIn post"
+    description = "Draft a post about customer success stories"
+
+    db_session.add(
+        TaskHistory(
+            user_id="user-1",
+            task_hash=service._compute_hash(title, description),
+            title=title,
+            description=description,
+            pillar_id="engage",
+            status="completed",
+            created_at=datetime.utcnow(),
+            vector_id="vec-exact",
+        )
+    )
+    db_session.commit()
+
+    proposals = [SimpleNamespace(title=title, description=description)]
+    filtered = await service.filter_redundant_proposals(proposals)
+
+    assert filtered == []
+
+
+@pytest.mark.asyncio
+async def test_filter_redundant_proposals_suppresses_semantic_dismissed_by_vector_id_lookup(db_session):
+    service = TaskMemoryService(user_id="user-2", db=db_session)
+    service.intelligence = SimpleNamespace(
+        search=AsyncMock(return_value=[{"id": "vec-dismissed", "score": 0.93}])
+    )
+
+    db_session.add(
+        TaskHistory(
+            user_id="user-2",
+            task_hash="hash-1",
+            title="Old task",
+            description="Old description",
+            pillar_id="plan",
+            status="dismissed",
+            created_at=datetime.utcnow(),
+            vector_id="vec-dismissed",
+        )
+    )
+    db_session.commit()
+
+    proposals = [
+        SimpleNamespace(
+            title="Plan daily content topics",
+            description="Choose 3 content ideas for this week",
+        )
+    ]
+
+    filtered = await service.filter_redundant_proposals(proposals)
+
+    assert filtered == []
+
+
+@pytest.mark.asyncio
+async def test_filter_redundant_proposals_keeps_non_duplicates(db_session):
+    service = TaskMemoryService(user_id="user-3", db=db_session)
+    service.intelligence = SimpleNamespace(
+        search=AsyncMock(return_value=[{"id": "vec-completed", "score": 0.40}])
+    )
+
+    proposal = SimpleNamespace(
+        title="Write newsletter intro",
+        description="Prepare a short intro for the weekly newsletter",
+    )
+    filtered = await service.filter_redundant_proposals([proposal])
+
+    assert filtered == [proposal]
+    service.intelligence.search.assert_awaited_once()