chore(deps): bump direct dependencies and remove unused ones

[het2576]

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Hey 👋

This PR updates only the direct dependencies in pyproject.toml and removes unnecessary ones that were added earlier.

What’s changed

• Kept only the dependencies actually used in code:
  • openai
  • python-dotenv
  • pyyaml
  • pydantic
• Removed transitive deps like httpx, tqdm, anyio, etc.
• Bumped all kept deps to their latest stable versions (Python ≥3.10 compatible)

Testing done

• Installed locally with pip install -e .
• Verified both frameworks:
  • agent-wiz extract --framework agent_chat ... ✅ works
  • agent-wiz extract --framework pydantic ... ✅ works
• agent-wiz visualize --input test_graph.json ✅ works
  (Note: --open fails in Codespaces because it can’t launch a browser — expected)

Everything installs and runs cleanly after the dependency cleanup.

Closes #35