Add README, config/logging, tests, and scheduling docs

[EcZachly]

To improve maintainability:

Tasks

• Add a README describing the trading workflow, data sources, and how to run locally.
• Centralize configuration (YAML + .env.example) and use logging instead of prints.
• Add pytest tests for scheduler/strategies and CI for lint/test.
• Provide a backtesting mode with a small sample dataset for safe verification.

Benefits

• Clear usage and safer iterations.