Without an explicit spring.datasource.url, Spring Boot falls back to
jdbc:postgresql://localhost:5432 when the SPRING_DATASOURCE_URL env var
is missing or not picked up. Default now points to the docker-compose
service name (postgres:5432/cameleer_saas).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>