Build container has no Docker-in-Docker, so TestContainers can't
create PostgreSQL containers. Exclude integration tests in CI;
they run locally with Docker Desktop. Matches cameleer3-server
pattern of separating unit and integration tests.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Use cameleer-build:1 (Maven 3.9 + Temurin 21) container instead of
setup-java. Use cameleer-docker-builder:1 for Docker image builds
with registry push. Aligns with cameleer3-server CI pattern.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
