NUnit integration tests that target a running API by URL and seed/clean
data directly in Postgres. Settings (BaseUrl, DbConnectionString) come
from .runsettings or environment variables so tests can be pointed at
any environment. HTTP requests live in HttpFiles/*.http; assertion
failures include a fresh DB snapshot of the relevant rows. First test
covers the flag-enabled path.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>