This commit adds:
- A unified configuration system (`AppConfig`) that aggregates KDL files and environment variables with precedence handling.
- Example KDL configuration files for the orchestrator and forge-integration modules.
- Updates to orchestrator and forge-integration to load and apply configurations from `AppConfig`.
- Improved AMQP and database configuration with overlays from CLI, environment, or KDL.
- Deprecated `TODO.txt` as it's now represented in the configuration examples.
