fix: pin tau2-bench to v0.2.0 to support Python 3.10/3.11

[xzrderek]

Summary

• The main branch of tau2-bench now ships tau2==0.2.1.dev0 which requires Python>=3.12,<3.14, breaking CI for Python 3.10 and 3.11 jobs
• Pins all tau2-bench installs to the v0.2.0 tag which still supports Python>=3.10
• Updates 5 install commands across ci.yml and e2e-smoke-test.yml, plus the UV source in pyproject.toml

Test plan

• Verify CI passes on Python 3.10, 3.11, and 3.12 matrix jobs
• Verify e2e smoke test workflow still runs successfully

Made with Cursor

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Note

Low Risk
Low risk: this only pins an external test dependency version in CI/workflows and uv source config, with no runtime or application logic changes.

Overview
Pins tau2-bench to the v0.2.0 tag instead of tracking main across CI and the scheduled E2E smoke test workflows.

Updates pyproject.toml ([tool.uv.sources]) to also lock tau2 to rev = "v0.2.0", keeping dependency resolution consistent and avoiding CI breakage from upstream Python version requirements.

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