chore: bump vllm to 0.20.2

[hallerite]

Summary

• Bump vllm requirement from >=0.20.1 to >=0.20.2
• Update pinned wheel URLs (x86_64 + aarch64) from v0.20.1 to v0.20.2
• Refresh uv.lock

🤖 Generated with Claude Code

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Note

Medium Risk
Updates a core inference/runtime dependency (vllm) and its pinned wheel artifacts, which could change model serving behavior or performance at runtime despite being a patch bump.

Overview
Updates the project’s vllm requirement to >=0.20.2 and switches the pinned vllm wheel URLs for both x86_64 and aarch64 to the v0.20.2 release.

Refreshes uv.lock to reflect the new vllm version/artifacts (including the lock’s exclude-newer timestamp) while leaving the rest of the dependency set effectively unchanged.

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