feat(libertas_api): add dependency on libertas_infra and async-nats
refactor(libertas_api): consolidate config loading and add broker_url
refactor(libertas_api): integrate NATS client into app state and services
feat(libertas_core): introduce config module for database and server settings
fix(libertas_core): enhance error handling with detailed messages
feat(libertas_infra): create infrastructure layer with database repositories
feat(libertas_infra): implement Postgres repositories for media and albums
feat(libertas_worker): add worker service to process media jobs via NATS
