feat: add support to custom providers

[ramonpaolo]

Description

This PR add the functionality to use custom providers/models to do the code review.

This PR allow the integration with local models, like Ollama, llama.cpp; and another providers/models like MiniMax M2.1

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactoring
• Other (please describe)

Checklist

• I have tested the changes
• My code follows the project's style guidelines
• I have commented my code where necessary
• I have made corresponding changes to the documentation
• My changes generate no new warnings

Related Issues

N/A

Additional Context

N/A

[github-actions]

undefined

---

Code review performed by CUSTOM - MiniMax-M2.1.

[github-actions]

🎯 Core Changes

This PR adds support for custom AI providers (like MiniMax M2.1, Ollama, llama.cpp) to the AI Code Review action. The changes include:

1. .github/workflows/code_review.yml: Updated workflow to use the new custom provider branch with MiniMax configuration instead of the local action with OpenAI
2. action.yml:
   • Added AI_BASE_URL input for custom provider endpoints
   • Made AI_API_KEY optional (previously required)
   • Updated AI_PROVIDER description to include "custom" option
   • Upgraded Node.js runtime from node20 to node24

⚠️ Concerns

• Missing documentation: The PR description doesn't mention that users need to add the AI_API_KEY secret when using custom providers. Consider documenting this requirement.
• API key optionality: Making AI_API_KEY optional in action.yml may cause confusing errors if a provider requires authentication but the user doesn't provide a key. Consider adding validation or clearer error messages.
• Node 24 runtime: Using node24 (which may not be fully stable) instead of the widely-used node20 could cause compatibility issues in some runner environments.

Verdict

The changes implement the stated feature correctly. The concerns above are minor and don't prevent merging. The PR author should consider documenting the new AI_API_KEY secret requirement for custom providers.

Suggested Action: comment

Confidence: 95

---

Code review performed by CUSTOM - MiniMax-M2.1.