One beforeEach Caused 36-Hour CI Failure in PostgreSQL Test Suite

A single beforeEach hook in a JavaScript test suite caused 36 hours of CI failures by truncating all 76 database tables before each of 1,140 tests, resulting in 86,640 truncate operations. The issue went unnoticed because local runs used test subsets and the pattern worked when the suite was smaller. The fix moved database sync to beforeAll and used transaction-based rollbacks instead of truncation.