Cold Postgres boot (connect + apply the full schema) takes a few seconds — the
fixed 300ms that was fine for SQLite's instant in-memory init raced the server
bind and the first fetch hit ECONNREFUSED. Poll BASE/ until it responds (≤30s).
Validated on local PostgreSQL 16: db-smoke 22/22 pass; e2e passes all DB-backed
checks (auth, messages, polls, groups, calls+invite, meetings) then stops at the
known pre-existing WS meeting-joined flake (unrelated to the DB).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>