Failed to find exact letter case of module name when relative import on Windows OS

Bug Report

Failed to find exact letter case of module name when relative import on Windows OS.

To Reproduce

ModuleName
├─ __init__.py
├─ file.py
├─ main.py

# main.py
from .file import *

Everything is fine when the path is correct with letter case.

mypy .\ModuleName\main.py
Success: no issues found in 1 source file

But if the path of files is wrong with letter case,

mypy .\moduleName\main.py

but there will be an [import-not-found] error.

moduleName\main.py:1: error: Cannot find implementation or library stub for module named "moduleName.file"  [import-not-found]

Your Environment

• Mypy version used: mypy 1.14.1 (compiled: yes)

首先使用 ModuleName/init.py、file.py 和 main.py 重现 Windows 的大小写不匹配问题，同时使用 main.py 中的相对导入和所示的两个 mypy 命令。跟踪命令行路径如何映射到模块名。完成的标准是：大小写不正确的路径能够解析相对导入，且不会出现 import-not-found 错误。