schema.js already had an uncommitted mqtt entry (host/port config,
username/password secrets) from a prior session — commits it now, adds
the missing test-connection case (routes/integrations.js), and the mqtt
package dependency it needs. The existing generic integration card UI in
portal's AdminSettings.tsx needs no changes — it renders any schema
entry automatically. initDb() auto-seeds the 'mqtt' row on next restart,
so the "MQTT Broker" card will appear in Settings -> Integrations.
Also adds a .gitignore — node_modules was untracked in this repo.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
