The server ledger is cleared by an explicit ack, never by the check-in response, so a dismissal that cannot reach the service must be persisted and retried or the device rings again later. Add a durable pending-ack queue (404 means the alert ended: settled, drop it), map the 409 ERR_ALARM_TRIGGERED_OFFLINE check-in into a normal trigger for the same takeover, and make a 404 an ending rather than a missed alarm. This also carries the expiry/endings state the screens render.
Apps reach every service through Maestro on one port; direct service addressing is no longer a supported deployment, and Maestro has no per-service hostname or host-port route. Replace the maestro/direct modes and the serviceRef lookup with one configured origin and the fixed paths /api/alarm/{action,auth,ws}, defaulting dev builds to 127.0.0.1:8080 through adb reverse. The old mode-specific body wrapping and the direct-mode socket branch go with it.