* fix: warn against using http_request for GitHub PR creation
- Root cause: http_request tool description and system prompt lacked explicit guidance not to use it for GitHub PR operations, causing the agent to fall back to it and receive 401 Unauthorized responses
- Change: added clear warnings to both the http_request docstring and the TOOL_USAGE_SECTION in prompt.py directing agents to use commit_and_open_pr instead
- Verified: docstring and prompt changes are minimal and scoped
* fix: clarify http_request PR guidance
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Co-authored-by: LangSmith Forge <forge-agent@langsmith.ai>
Co-authored-by: Johannes du Plessis <johannes@langchain.dev>