fix: add missing dependency sniffio

[guuzaa]

Description

Added missing dependency sniffio.

Fixes #53

[Copilot]

Pull request overview

This PR adds sniffio as an explicit dependency to fix issue #53. The library is imported and used in src/zai/core/_utils/_utils.py for detecting the current async library, but was previously only available as a transitive dependency through httpx → anyio → sniffio.

Changes:

• Added sniffio = "^1.3.1" to the main dependencies in pyproject.toml
• Updated poetry.lock with new content hash reflecting the dependency change

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

File	Description
pyproject.toml	Added sniffio as an explicit dependency to ensure it's available when imported directly
poetry.lock	Updated lock file with new content hash; Poetry version also updated from 2.1.4 to 2.2.1

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[guuzaa]

You should re-run poetry lock to update poetry.lock.
In my opinion, ^ is a better choice than >=. ^ means versions that won't break backward compatibility, while >= means any version equal to or higher than 1.3.1 including breaking changes.

[tomsun28]

You should re-run poetry lock to update poetry.lock. In my opinion, ^ is a better choice than >=. ^ means versions that won't break backward compatibility, while >= means any version equal to or higher than 1.3.1 including breaking changes.

hi, suggest keeping it consistent with others. and avoid cases where multiple version ranges have no intersection.