refactor(financial-sync): 重构财务数据同步架构

- 新增 base_financial_sync.py 基础同步抽象类
- 重构 api_financial_sync.py 简化调度逻辑
- 重命名 IncomeSync 为 IncomeQuarterSync 继承新基础类
- 增强 storage.py 支持 use_upsert 参数
- 更新 __init__.py 导出符号

src/data/api_wrappers/__init__.py

@@ -47,7 +47,8 @@ from src.data.api_wrappers.api_pro_bar import (
 from src.data.api_wrappers.financial_data.api_income import (
     get_income,
     sync_income,
-    IncomeSync,
+    preview_income_sync,
+    IncomeQuarterSync,
 )
 from src.data.api_wrappers.api_bak_basic import get_bak_basic, sync_bak_basic
 from src.data.api_wrappers.api_namechange import get_namechange, sync_namechange
@@ -84,7 +85,8 @@ __all__ = [
     # Income statement
     "get_income",
     "sync_income",
-    "IncomeSync",
+    "preview_income_sync",
+    "IncomeQuarterSync",
     # Historical stock list
     "get_bak_basic",
     "sync_bak_basic",