refactor: remove Excel migration pipeline; keep Access-only sync

Drop the Excel (.xlsm) production-execution-card pipeline now that the
project only synchronizes Access databases to SQL Server.

- Delete excel_sync_to_sql.py, migration.py, config/field_mappings.py
- Remove Excel-only config symbols (EXCEL_CONFIGS, MIGRATION_TASKS,
  EXECUTION_CARD_FIELDS, CONTRACT_DATA_*, CACHE_DIR, TEMP_DIR,
  EXCEL_SYNC_* settings) from the config package
- Drop now-unused deps from requirements.txt: pandas, sqlalchemy, openpyxl
- Update .env.example, CLAUDE.md, and the uptime_kuma_utils docstring
- Fix the tube-bending workshop Access table mapping in SYNC_MAPPING
  (source table renamed; old name no longer exists)

The three Excel-sourced tables in warehouseOutbound (executionCardData,
contractData, customerProductType) and their data are left untouched.

Co-Authored-By: Claude <noreply@anthropic.com>

config/__init__.py

@@ -7,17 +7,13 @@ load_dotenv()
 # 数据库配置
 from .database import SQL_SERVER_CONFIG, SQL_SERVER_CONN, DB_CONFIG, ACCESS_DRIVER
 
-# 文件路径配置
-from .file_sources import SYNC_MAPPING, EXCEL_CONFIGS, MIGRATION_TASKS
-
-# 字段映射配置
-from .field_mappings import TABLE_SCHEMA, CONTRACT_MAPPING
+# 文件路径配置（Access 同步映射）
+from .file_sources import SYNC_MAPPING
 
 # 应用设置
 from .app_settings import (
-    LOG_TABLE_CONFIG, NTFY_CONFIG, UPTIME_KUMA_CONFIG, EXCEL_SYNC_UPTIME_KUMA_CONFIG,
-    POLL_INTERVAL, EXCEL_SYNC_INTERVAL, BATCH_SIZE, CACHE_DIR, TEMP_DIR,
-    EXECUTION_CARD_FIELDS, CONTRACT_DATA_FIELDS, CONTRACT_DATA_MAPPING
+    LOG_TABLE_CONFIG, NTFY_CONFIG, UPTIME_KUMA_CONFIG,
+    POLL_INTERVAL, BATCH_SIZE,
 )
 
 # 统一导出列表
@@ -25,11 +21,8 @@ __all__ = [
     # Database
     'SQL_SERVER_CONFIG', 'SQL_SERVER_CONN', 'DB_CONFIG', 'ACCESS_DRIVER',
     # File Sources
-    'SYNC_MAPPING', 'EXCEL_CONFIGS', 'MIGRATION_TASKS',
-    # Field Mappings
-    'TABLE_SCHEMA', 'CONTRACT_MAPPING',
+    'SYNC_MAPPING',
     # App Settings
-    'LOG_TABLE_CONFIG', 'NTFY_CONFIG', 'UPTIME_KUMA_CONFIG', 'EXCEL_SYNC_UPTIME_KUMA_CONFIG',
-    'POLL_INTERVAL', 'EXCEL_SYNC_INTERVAL', 'BATCH_SIZE', 'CACHE_DIR', 'TEMP_DIR',
-    'EXECUTION_CARD_FIELDS', 'CONTRACT_DATA_FIELDS', 'CONTRACT_DATA_MAPPING'
+    'LOG_TABLE_CONFIG', 'NTFY_CONFIG', 'UPTIME_KUMA_CONFIG',
+    'POLL_INTERVAL', 'BATCH_SIZE',
 ]