Add request/response logging to file

[bimakw]

Description

Log all requests and responses to a file for debugging and audit purposes.

Requirements

• Log request: method, path, headers, client IP, timestamp
• Log response: status code, duration, response size
• Support configurable log file path
• Implement log rotation (optional)

Acceptance Criteria

• All requests logged with relevant details
• Response time and status captured
• Log file path configurable via environment variable
• Sensitive headers (Authorization) redacted