Fixes#4088
The GithubSearchTool was unable to access private repositories because
the CrewAIRagAdapter.add() method was not passing kwargs (including
metadata with gh_token) to the loader.load() call.
This fix ensures that kwargs are properly forwarded to the loader,
allowing the GithubLoader to receive the gh_token for authentication.
Added tests:
- test_github_loader.py: Unit tests for GithubLoader
- test_crewai_rag_adapter.py: Tests for kwargs passthrough in adapter
Co-Authored-By: João <joao@crewai.com>
