fix(memory): make PgSQL the single source of truth for user entity aliases

- Skip alias merging for user entities during dedup (_merge_attribute and
  _merge_entities_with_aliases) to prevent dirty data from overwriting
  PgSQL authoritative aliases
- Add PgSQL→Neo4j alias sync after Neo4j write in write_tools to
  ensure Neo4j user entities always reflect the PgSQL source
- Remove deduped_aliases (Neo4j history) from alias sync in
  extraction_orchestrator, only append newly extracted aliases to PgSQL
- Guard Neo4j MERGE cypher to preserve existing aliases for user
  entities (name IN ['用户','我','User','I'])
- Fix emotion_analytics_service query to use ExtractedEntity label
  and entity_type property

api/app/repositories/neo4j/cypher_queries.py

@@ -93,6 +93,8 @@ SET e.name = CASE WHEN entity.name IS NOT NULL AND entity.name <> '' THEN entity
     END,
     e.statement_id = CASE WHEN entity.statement_id IS NOT NULL AND entity.statement_id <> '' THEN entity.statement_id ELSE e.statement_id END,
     e.aliases = CASE
+        // 用户实体的 aliases 由 PgSQL end_user_info 作为唯一权威源，知识抽取完全不写入
+        WHEN entity.name IN ['用户', '我', 'User', 'I'] THEN e.aliases
         WHEN entity.aliases IS NOT NULL AND size(entity.aliases) > 0
         THEN CASE 
             WHEN e.aliases IS NULL THEN entity.aliases