-- Preserve message outbox lease and provider result metadata across restarts.
ALTER TABLE IF EXISTS email_sms_outbox
  ADD COLUMN IF NOT EXISTS lease_owner TEXT,
  ADD COLUMN IF NOT EXISTS lease_expires_at TIMESTAMPTZ,
  ADD COLUMN IF NOT EXISTS provider_message_id TEXT,
  ADD COLUMN IF NOT EXISTS last_error TEXT,
  ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT now();
CREATE INDEX IF NOT EXISTS email_sms_outbox_poll_idx
  ON email_sms_outbox(status, next_attempt_at);