feat: 新增 JSONL 存储格式支持，默认存储格式改为 jsonl

JSONL（JSON Lines）每行一个 JSON 对象，采用 append 模式写入，
无需读取已有数据，大数据量下性能远优于 JSON 格式。

- 新增 AsyncFileWriter.write_to_jsonl() 核心方法
- 7 个平台新增 JsonlStoreImplement 类并注册到工厂
- 配置默认值从 json 改为 jsonl，CLI/API 枚举同步更新
- db_session.py 守卫条件加入 jsonl，避免误触 ValueError
- 词云生成支持读取 JSONL 文件，优先 jsonl 回退 json
- 原有 json 选项完全保留，向后兼容
- 更新相关文档和测试

tests/test_store_factory.py

@@ -1,4 +1,21 @@
 # -*- coding: utf-8 -*-
+# Copyright (c) 2025 relakkes@gmail.com
+#
+# This file is part of MediaCrawler project.
+# Repository: https://github.com/NanmiCoder/MediaCrawler/blob/main/tests/test_store_factory.py
+# GitHub: https://github.com/NanmiCoder
+# Licensed under NON-COMMERCIAL LEARNING LICENSE 1.1
+#
+# 声明：本代码仅供学习和研究目的使用。使用者应遵守以下原则：
+# 1. 不得用于任何商业用途。
+# 2. 使用时应遵守目标平台的使用条款和robots.txt规则。
+# 3. 不得进行大规模爬取或对平台造成运营干扰。
+# 4. 应合理控制请求频率，避免给目标平台带来不必要的负担。
+# 5. 不得用于任何非法或不当的用途。
+#
+# 详细许可条款请参阅项目根目录下的LICENSE文件。
+# 使用本代码即表示您同意遵守上述原则和LICENSE中的所有条款。
+
 """
 Unit tests for Store Factory functionality
 """
@@ -10,6 +27,7 @@ from store.xhs import XhsStoreFactory
 from store.xhs._store_impl import (
     XhsCsvStoreImplement,
     XhsJsonStoreImplement,
+    XhsJsonlStoreImplement,
     XhsDbStoreImplement,
     XhsSqliteStoreImplement,
     XhsMongoStoreImplement,
@@ -19,57 +37,63 @@ from store.xhs._store_impl import (
 
 class TestXhsStoreFactory:
     """Test cases for XhsStoreFactory"""
-    
+
     @patch('config.SAVE_DATA_OPTION', 'csv')
     def test_create_csv_store(self):
         """Test creating CSV store"""
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsCsvStoreImplement)
-    
+
     @patch('config.SAVE_DATA_OPTION', 'json')
     def test_create_json_store(self):
         """Test creating JSON store"""
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsJsonStoreImplement)
-    
+
     @patch('config.SAVE_DATA_OPTION', 'db')
     def test_create_db_store(self):
         """Test creating database store"""
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsDbStoreImplement)
-    
+
     @patch('config.SAVE_DATA_OPTION', 'sqlite')
     def test_create_sqlite_store(self):
         """Test creating SQLite store"""
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsSqliteStoreImplement)
-    
+
     @patch('config.SAVE_DATA_OPTION', 'mongodb')
     def test_create_mongodb_store(self):
         """Test creating MongoDB store"""
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsMongoStoreImplement)
-    
+
     @patch('config.SAVE_DATA_OPTION', 'excel')
     def test_create_excel_store(self):
         """Test creating Excel store"""
         # ContextVar cannot be mocked, so we test with actual value
         store = XhsStoreFactory.create_store()
         assert isinstance(store, XhsExcelStoreImplement)
-    
+
+    @patch('config.SAVE_DATA_OPTION', 'jsonl')
+    def test_create_jsonl_store(self):
+        """Test creating JSONL store"""
+        store = XhsStoreFactory.create_store()
+        assert isinstance(store, XhsJsonlStoreImplement)
+
     @patch('config.SAVE_DATA_OPTION', 'invalid')
     def test_invalid_store_option(self):
         """Test that invalid store option raises ValueError"""
         with pytest.raises(ValueError) as exc_info:
             XhsStoreFactory.create_store()
-        
+
         assert "Invalid save option" in str(exc_info.value)
-    
+
     def test_all_stores_registered(self):
         """Test that all store types are registered"""
-        expected_stores = ['csv', 'json', 'db', 'sqlite', 'mongodb', 'excel']
-        
+        expected_stores = ['csv', 'json', 'jsonl', 'db', 'postgres', 'sqlite', 'mongodb', 'excel']
+
         for store_type in expected_stores:
             assert store_type in XhsStoreFactory.STORES
-        
+
         assert len(XhsStoreFactory.STORES) == len(expected_stores)