feat(memory): add alias invalidation support for entity alias management

Introduce the `别名失效` predicate to handle cases where an alias is
explicitly no longer applicable to an entity.

Changes:
- write_pipeline.py: extend _merge_alias_in_memory to process
  `别名失效` edges — removes invalidated alias names from target
  entity's aliases list in-memory before Neo4j write
- cypher_queries.py: add REMOVE_INVALID_ALIASES and DELETE_ALIAS_NODES
  queries; update REDIRECT_ALIAS_EDGES to handle both `别名属于` and
  `别名失效` predicates
- tasks.py: add step 1.5 in post_store_dedup_and_alias_merge_task to
  execute REMOVE_INVALID_ALIASES and sync removals to PostgreSQL;
  add step 3 to delete alias nodes after edge redirection; add
  snapshot step 3.5 for post-merge entity state; pass snapshot_dir
  to the task
- end_user_info_repository.py: add remove_aliases() method to remove
  specified aliases from end_user_info.aliases (case-insensitive)
- write_snapshot_recorder.py: add save_alias_merge_result() static
  method to write stage 8 snapshot after alias merge and deletion
- extract_triplet.jinja2: document `别名失效` predicate with usage
  rules — only use when conversation explicitly negates an alias

api/app/repositories/end_user_info_repository.py

@@ -138,3 +138,41 @@ class EndUserInfoRepository:
                 f"aliases_count={len(end_user_info.aliases or [])}"
             )
         return end_user_info
+
+    def remove_aliases(
+        self,
+        end_user_id: uuid.UUID,
+        aliases_to_remove: List[str],
+    ) -> Optional["EndUserInfo"]:
+        """从用户别名列表中移除指定别名（忽略大小写）。
+
+        Args:
+            end_user_id: 终端用户 ID
+            aliases_to_remove: 需要移除的别名列表
+
+        Returns:
+            更新后的 EndUserInfo，若记录不存在则返回 None
+        """
+        if not aliases_to_remove:
+            return self.get_by_end_user_id(end_user_id)
+
+        end_user_info = self.get_by_end_user_id(end_user_id)
+        if not end_user_info:
+            logger.warning(f"[EndUserInfo] 记录不存在，跳过别名移除: end_user_id={end_user_id}")
+            return None
+
+        remove_lower = {a.strip().lower() for a in aliases_to_remove if a.strip()}
+        existing = list(end_user_info.aliases or [])
+        new_aliases = [a for a in existing if a.lower() not in remove_lower]
+
+        if len(new_aliases) == len(existing):
+            return end_user_info
+
+        end_user_info.aliases = new_aliases
+        self.db.commit()
+        self.db.refresh(end_user_info)
+        logger.info(
+            f"[EndUserInfo] 别名移除完成: end_user_id={end_user_id}, "
+            f"removed={aliases_to_remove}, remaining={new_aliases}"
+        )
+        return end_user_info

api/app/repositories/neo4j/cypher_queries.py

@@ -1379,16 +1379,16 @@ RETURN source.name AS merged_alias, target.name AS target_name, new_aliases AS u
 #   2. STATEMENT_ENTITY：陈述句 → 别名节点
 # 对于每条需要重定向的边，创建一条指向用户节点的新边（复制所有属性），然后删除旧边。
 REDIRECT_ALIAS_EDGES = """
-// 找到所有 别名→用户 的映射
+// 找到所有 别名→用户 的映射（包含 别名属于 和 别名失效 两种 predicate）
 MATCH (alias:ExtractedEntity {end_user_id: $end_user_id})-[ar:EXTRACTED_RELATIONSHIP]->(user:ExtractedEntity {end_user_id: $end_user_id})
-WHERE ar.predicate = '别名属于'
+WHERE ar.predicate IN ['别名属于', '别名失效']
 WITH collect({alias_id: elementId(alias), user_id: elementId(user), alias_eid: alias.id, user_eid: user.id}) AS mappings
 
 // 1. 重定向 EXTRACTED_RELATIONSHIP 边：别名节点作为 target 的情况
 UNWIND mappings AS m
 MATCH (other)-[r:EXTRACTED_RELATIONSHIP]->(alias:ExtractedEntity {end_user_id: $end_user_id})
 WHERE alias.id = m.alias_eid
-  AND r.predicate <> '别名属于'
+  AND NOT (r.predicate IN ['别名属于', '别名失效'])
   AND other.id <> m.user_eid
 WITH m, other, r, alias
 MATCH (user:ExtractedEntity {id: m.user_eid, end_user_id: $end_user_id})
@@ -1399,10 +1399,10 @@ WITH count(*) AS redirected_incoming
 
 // 2. 重定向 EXTRACTED_RELATIONSHIP 边：别名节点作为 source 的情况
 MATCH (alias:ExtractedEntity {end_user_id: $end_user_id})-[ar2:EXTRACTED_RELATIONSHIP]->(user2:ExtractedEntity {end_user_id: $end_user_id})
-WHERE ar2.predicate = '别名属于'
+WHERE ar2.predicate IN ['别名属于', '别名失效']
 WITH alias, user2, redirected_incoming
 MATCH (alias)-[r:EXTRACTED_RELATIONSHIP]->(other)
-WHERE r.predicate <> '别名属于'
+WHERE NOT (r.predicate IN ['别名属于', '别名失效'])
   AND other.id <> user2.id
 WITH user2, other, r, redirected_incoming
 CREATE (user2)-[nr:EXTRACTED_RELATIONSHIP]->(other)
@@ -1412,7 +1412,7 @@ WITH redirected_incoming, count(*) AS redirected_outgoing
 
 // 3. 重定向 STATEMENT_ENTITY 边：陈述句 → 别名节点
 MATCH (alias:ExtractedEntity {end_user_id: $end_user_id})-[ar3:EXTRACTED_RELATIONSHIP]->(user3:ExtractedEntity {end_user_id: $end_user_id})
-WHERE ar3.predicate = '别名属于'
+WHERE ar3.predicate IN ['别名属于', '别名失效']
 WITH alias, user3, redirected_incoming, redirected_outgoing
 MATCH (stmt)-[r:STATEMENT_ENTITY]->(alias)
 WITH user3, stmt, r, redirected_incoming, redirected_outgoing
@@ -1423,6 +1423,32 @@ DELETE r
 RETURN redirected_incoming, redirected_outgoing, count(*) AS redirected_stmt
 """
 
+# 删除别名节点：在别名归并和边重定向完成后，删除所有 predicate="别名属于" 关系的 source 节点。
+# 此时这些节点的其他边已被 REDIRECT_ALIAS_EDGES 重定向完毕，
+# 唯一剩余的边就是 (alias)-[:EXTRACTED_RELATIONSHIP {predicate:'别名属于'}]->(user)，
+# 使用 DETACH DELETE 一并删除节点和该关系。
+DELETE_ALIAS_NODES = """
+MATCH (alias:ExtractedEntity {end_user_id: $end_user_id})-[r:EXTRACTED_RELATIONSHIP]->(user:ExtractedEntity {end_user_id: $end_user_id})
+WHERE r.predicate IN ['别名属于', '别名失效']
+WITH alias, count(r) AS rel_count
+DETACH DELETE alias
+RETURN count(alias) AS deleted_count
+"""
+
+# 失效别名处理：将 predicate="别名失效" 的 source.name 从 target.aliases 中移除。
+# 在 MERGE_ALIAS_BELONGS_TO（追加新别名）之后、DELETE_ALIAS_NODES（删除节点）之前执行。
+REMOVE_INVALID_ALIASES = """
+MATCH (source:ExtractedEntity {end_user_id: $end_user_id})-[r:EXTRACTED_RELATIONSHIP]->(target:ExtractedEntity {end_user_id: $end_user_id})
+WHERE r.predicate = '别名失效'
+WITH source, target,
+     coalesce(target.aliases, []) AS existing_aliases,
+     source.name AS invalid_name
+
+SET target.aliases = [a IN existing_aliases WHERE toLower(a) <> toLower(invalid_name)]
+
+RETURN source.name AS removed_alias, target.name AS target_name
+"""
+
 CHECK_COMMUNITY_IS_COMPLETE_WITH_EMBEDDING = """
 MATCH (c:Community {community_id: $community_id, end_user_id: $end_user_id})
 RETURN (