fix: resolve all CI mypy (265→0) and ruff (26→0) errors

- pyproject.toml: add mypy overrides for pandas/tabulate/matplotlib stubs,
  disable strict checking for vendored MyTT library
- config.py: use cast() for dict[str, Any] .get() returns
- beichi.py: widen _calc_bi_force param to BI | XD, import XD
- backtest/cli.py: split combo/single strategy into separate typed variables
- backtest/combo.py: add bool_array() helper for numpy return types
- chanlun/analyser.py: type ignore for pandas row access, fix dict type arg
- unified.py: change fields param from object to Any
- ex/mac_client.py: add type args to list literals
- cli/cmd_offline.py: wrap int market as Market enum before API call
- cli/cmd_chanlun.py: fix dict type arg
- offline/write_*.py: explicit int() cast for struct.unpack returns
- MyTT.py: fix line-too-long comments, UP038 isinstance syntax
- tests: fix E712 (==False → ~mask), E741 (noqa), F841, import sorting
- ruff format applied across codebase

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/easy_tdx/commands/security_list.py

@@ -39,10 +39,10 @@ class GetSecurityListCmd(BaseCommand[list[SecurityInfo]]):
                 code_bytes,
                 volunit,
                 name_bytes,
-                _unknown1,    # 4字节，排序/分组字段（非用户可见数据）
+                _unknown1,  # 4字节，排序/分组字段（非用户可见数据）
                 decimal_point,
                 pre_close_raw,
-                _unknown2,    # 4字节，私有时间戳（非用户可见数据）
+                _unknown2,  # 4字节，私有时间戳（非用户可见数据）
             ) = struct.unpack("<6sH8s4sBI4s", raw)
 
             code = code_bytes.decode("utf-8", errors="replace").rstrip("\x00")