[BUG] Missing `Union, Optional, Tuple, etc.` imports in `__init__.pyi` leads to Unknown type hints

[XXXXRT666]

Describe the bug
Missing Union, Optional, scalar, Tuple in __init__.pyi

Desktop (please complete the following information):

• OS Version: macOS 15
• Version 0.28.0

[XXXXRT666]

Also, the return type does not match the documentation, so I had to cast it to satisfy the type checker

[LA-10]

Can you please clarify the file path of __init__.pyi?

[XXXXRT666]

I think there is only one .pyi file generated in setup.py as the type stub for mlx.core.