Add structured logging to satoshi-mediator #117
Description
Summary
Replace console.log/error calls in satoshi-mediator with structured logging.
Motivation
- Machine-parseable JSON output instead of flat strings
- Log levels (debug/info/warn/error) to control verbosity per environment
- Context objects (errors, state) attached as fields instead of flattened into strings
- Better integration with the existing Grafana/Prometheus monitoring stack
Scope
services/mediators/satoshi/src/satoshi-mediator.ts — approximately 30+ console.log/error calls to convert.