fix: avoid vulnerable LiteLLM versions

[DougButdorf]

Summary

• Rebase on current upstream main.
• Keep upstream's existing pyproject.toml / uv.lock LiteLLM fix: litellm>=1.83.7,<2, lockfile litellm==1.83.14.
• Update the Homebrew formula resource from vulnerable litellm-1.83.0 to non-vulnerable litellm-1.83.14.

Why

GitHub advisory GHSA-r75f-5x8p-qvmc / CVE-2026-42208 affects LiteLLM >=1.81.16, <1.83.7. The formula resource was still vendoring 1.83.0, which is inside that range.

Verification

• Confirmed no conflict markers.
• Confirmed no vulnerable LiteLLM range remains in pyproject.toml, uv.lock, or Formula/skill-scanner.rb.
• uv run --python 3.13 pytest -q
• Result: 1300 passed, 5 skipped, 20 warnings.

[joshlembergtrimble]

The current LiteLLM version is causing breaking changes in our systems using this repo. Can we get this reviewed and merged? I see @vineethsai7 has contributed to this repo a lot recently, and @sanket-mendapara as well, maybe they can review?