feat(provider): Add Groq as a supported inference provider

[khaile]

Summary

Add Groq as a supported inference provider, enabling users to use Groq's API for LLM inference within OpenShell sandboxes.

Changes

• Added new Groq provider plugin in crates/openshell-providers/src/providers/groq.rs
• Registered Groq in the provider discovery system
• Added necessary inference profile configuration

Testing

• mise run pre-commit passes
• Unit tests pass
• E2E tests added/updated (if applicable)

Checklist

• Follows Conventional Commits
• Commits are signed off (DCO)
• Architecture docs updated (if applicable)

[github-actions]

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[github-actions]

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