6a2a5a6018
Adds an optional `stderr` parameter to sanitize_agent_error(). When provided, up to 1 KB of stderr text is included in the A2A error response after sanitization (API keys / bearer tokens ≥20 chars / long paths redacted). The existing generic form is preserved when stderr is absent. Updates both the main a2a_executor and the google-adk adapter. Closes: roadmap item — SDK executor stderr swallowing. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>