[dvd233]

Description

Fixes #103.

The ~=2.8.0 PyJWT constraint excludes every 2.9+ release, conflicting with the pyjwt>=2.9.0 requirement reported for langgraph-api. Allow >=2.8.0,<3.0.0 so compatible 2.x releases can be selected while retaining the existing minimum and excluding a future major version. Token generation and all other dependencies are unchanged.

Validation on Python 3.10.8:

• Built baseline and updated wheels with Poetry Core 1.9.0. The emitted PyJWT requirement changes from <2.9.0 to <3.0.0; packaged runtime files are byte-identical.
• Ran the unmodified token generator with PyJWT 2.8.0, 2.9.0, 2.10.1 and 2.15.1: identical deterministic tokens, signature verification, invalid-key rejection and cache reuse passed.
• Installed the updated wheel into an isolated local directory and exercised real SDK chat requests through httpx.MockTransport with both token-cache modes on all four versions (8 cases); request headers/body and response parsing passed.
• git diff --check passed. No live API calls, full SDK test suite or full LangGraph joint installation was run. Python 3.8 was not executed; PyPI metadata allows PyJWT 2.9.0 on it.

PyJWT 2.15.1 warns for the existing 7-byte synthetic test key; signing still succeeds. The strong-key request cases run without warnings. This does not suppress or change PyJWT's warning behavior.

• Followed the contributing guide and Conventional Commits title format.
• No API documentation change needed for this dependency constraint update.