🏷️ Annotate einsum_path return type (Issue #724)

[pareshjoshij]

Closes #724

Summary
This PR adds precise type annotations for the return value of np.einsum_path.

Changes

• Updated _OptimizeKind to include Sequence[str | tuple[int, ...]].
• Updated einsum_path return type to tuple[list[str | tuple[int, ...]], str].
• Added a static regression test case in src/numpy-stubs/@test/static/accept/test_einsum_path.py.

Verification
I verified the changes statically with mypy and confirmed the runtime behavior matches the new annotation.

1. Static Check (Mypy)

Success: no issues found in 1 source file

[pareshjoshij]

@jorenham sir I tried running this locally and got results with different lengths like (0,) for size 1 and others for size 2). I used ... to be safe since it seems variable, but please let me know if there's a better way to handle that.

Also, I noticed the CLI checks failed on the existing tests—should I just update those files to match this new type?

[jorenham]

I tried running this locally and got results with different lengths like (0,) for size 1 and others for size 2). I used ... to be safe since it seems variable, but please let me know if there's a better way to handle that.

Ah I see... It's a bit unfortunate, but nothing to lose sleep over 🤷. Anyway, tuple[int, ...] is then indeed the right way to go here

Also, I noticed the CLI checks failed on the existing tests—should I just update those files to match this new type?

Yea it's better to update those instead of writing new ones then.

[pareshjoshij]

@jorenham sir Expert advice needed! 🏳️

The Linter and Formatter seem to be at war over these long lines. Every time I appease one, the other gets angry. 🤯

[jorenham]

The Linter and Formatter seem to be at war over these long lines. Every time I appease one, the other gets angry. 🤯

Running uv run ruff check --fix could help

[pareshjoshij]

The Linter and Formatter seem to be at war over these long lines. Every time I appease one, the other gets angry. 🤯

Running uv run ruff check --fix could help

Done

[jorenham]

Thanks @pareshjoshij