Refactor configuration management and remove deprecated files

- Consolidated database, file source, and field mapping configurations into dedicated modules under the `config` directory.
- Removed hardcoded database connection details from `migration.py` and replaced them with imports from the new configuration structure.
- Updated `ntfy_utils.py` and `run_incremental_sync.py` to utilize the new configuration imports for cleaner code and better maintainability.
- Deleted `update_config.py` as its contents have been integrated into the new configuration files.
- Added a new `settings.local.json` for managing permissions related to script execution.
- Enhanced the structure of the migration tasks and Excel configurations for better organization and clarity.

config/database.py

@@ -0,0 +1,30 @@
+# config/database.py
+# 统一的数据库配置
+
+# ================= SQL Server 配置 =================
+SQL_SERVER_CONFIG = {
+    'driver': 'ODBC Driver 18 for SQL Server',
+    'server': '192.168.110.114',
+    'database': 'CompanyDB',
+    'username': 'peng',
+    'password': 'Cqbld123456.',
+    'trust_server_certificate': 'yes'
+}
+
+# ================= Access 驱动配置 =================
+ACCESS_DRIVER = "{Microsoft Access Driver (*.mdb, *.accdb)}"
+
+# ================= 兼容性别名 =================
+# 为了兼容旧代码，提供不同命名风格的别名
+
+# SQL_SERVER_CONN - 兼容 db_utils.py (使用 uid/pwd)
+SQL_SERVER_CONN = {
+    'driver': f"{{{SQL_SERVER_CONFIG['driver']}}}",
+    'server': SQL_SERVER_CONFIG['server'],
+    'database': SQL_SERVER_CONFIG['database'],
+    'uid': SQL_SERVER_CONFIG['username'],
+    'pwd': SQL_SERVER_CONFIG['password']
+}
+
+# DB_CONFIG - 兼容 etl_manager.py, migration.py (使用 username/password)
+DB_CONFIG = SQL_SERVER_CONFIG.copy()