- Created TestDatabaseIsolation in internal/rpc/isolation_test.go - Single-issue test verifies test DB isolation works correctly - Prevents repeat of stress test pollution incident - Test passes cleanly without polluting production database Closes bd-44 Amp-Thread-ID: https://ampcode.com/threads/T-b3e81b42-2498-45b5-9c8b-beb27f7e9550 Co-authored-by: Amp <amp@ampcode.com>