regression-env: refuse compose-era test DB URLs (localhost:543x / *_test_db) instead of reachability timeout #696

Problem

ADR 0038 retired docker-compose: all test databases are in-memory pglite, and CI no longer runs postgres. But a compose-era URL can still sneak into .env.test (or .env) and the current dev-data guard does not catch it.

What happened in practice (PR #403): a new plugin's .env.test entry carried a stale compose-era test URL —

AGENT_CONNECT_DATABASE_URL=postgres://everythingdev:everythingdev@localhost:5434/api_test_db

The regression suite resolved it, waitForDatabases (tests/regression/lib/start-stack.mjs) probed localhost:5434, found nothing listening (line removed from CI), and every regression job failed after its full retry budget with:

Error: test databases not reachable: localhost:5434 ...

Why the guard missed it

legacyDevDatabaseUrl in tests/regression/lib/regression-env.mjs refuses only the dev-data shapes:

• pglite dev default (pglite:.bos/db)
• postgres on localhost with user/pass everythingdev:everythingdev and db name exactly api_db or auth_db

api_test_db on port 5434 passes that check, so instead of a fail-fast refusal the run dies on a slow reachability timeout with no pointer at the actual mistake.

Proposal

Teach the guard to also classify compose-era test DB URLs and refuse them (with the same override escape hatch, REGRESSION_ALLOW_DEV_DB=1):

• localhost postgres URLs pointing at the compose-era test ports/hosts (5432–5435 range on localhost/127.0.0.1)
• db names matching the compose-test convention (api_test_db, auth_test_db, and any *_test_db)

The refusal message should point at the fix: regenerate .env.test via pnpm run bos dev, or set the secret to pglite::memory: per ADR 0038.

Reference

• PR feat(agents): agent-connect plugin — owner-controlled agent accounts on the NEAR Intents Agent API #403 incident: fix(agent-connect): .env.test routes the plugin database to in-memory pglite (ADR 0038) (commit d620e39)
• Guard lives in tests/regression/lib/regression-env.mjs (isDevDatabaseUrl / legacyDevDatabaseUrl)
• Timeout lives in tests/regression/lib/start-stack.mjs (waitForDatabases)