fix: resolve CI failures — lint errors, pytz in redis, lockfile mismatch

- Remove unused imports: get_update_memory_messages, get_fact_retrieval_messages
- Fix pytz.timezone("US/Pacific") → timezone.utc in redis vector store
- Remove unused entity_types variable in test_entity_extraction
- Regenerate pnpm-lock.yaml after neo4j-driver removal

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/utils/test_entity_extraction.py

@@ -17,7 +17,6 @@ class TestExtractEntities:
 
         entities = extract_entities("John Smith works at Google on machine learning projects")
         entity_texts = [e[1] for e in entities]
-        entity_types = [e[0] for e in entities]
         # Should extract proper nouns
         found_proper = any("John" in t or "Google" in t for t in entity_texts)
         assert found_proper, f"Expected proper nouns, got {entities}"