Problem: Debug Log Buffer Functionality Removed

The previous logger implementation was writing log records to debug/log.DefaultLog, which maintained an in-memory buffer of logs. This buffer was used by the Debug handler to provide a Debug.Log endpoint for querying logs.

When the logger was replaced with slog, this functionality was removed.

Plan to Restore Functionality

• Analyze the issue
  • Review original logger implementation
  • Understand debug/log package purpose
  • Identify Debug.Log endpoint dependency
  • Understand how logs were buffered
• Design slog-compatible solution
  • Create slog handler that writes to debug/log buffer
  • Integrate handler with logger initialization
  • Maintain backward compatibility
• Implement the fix
  • Create custom slog handler
  • Update logger to use multi-handler approach
  • Ensure both stdout and debug buffer receive logs
• Test the implementation
  • Test debug log endpoint works
  • Test log buffering and retrieval
  • Test streaming logs
  • Verify existing tests still pass
• Code review and validation
  • Request code review
  • Address code review feedback
  • Run security checks

Solution Implemented

Created a multi-handler approach for slog:

1. debugLogHandler - writes log records to debug/log.DefaultLog buffer with metadata and source info
2. multiHandler - combines text handler (stdout) and debug handler
3. Both handlers receive all log records, maintaining original functionality

Code improvements:

• Extracted extractSourceFilePath helper to eliminate duplication
• Removed unused buildFormattedOutput function

Testing & Validation

✅ All existing tests pass
✅ New tests verify debug buffer functionality
✅ Integration tests confirm logs are buffered correctly
✅ Debug.Log endpoint can read logs from buffer
✅ Fields and metadata are preserved
✅ No security vulnerabilities detected

All functionality restored with zero breaking changes!

• Fixes [FEATURE] Remove logger #2781

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