Get a list of user devices registered by the mobile app.

Devices are created when the mobile app first communicates with the platform.
A user can have multiple devices (one per device where they are logged in).
The association is removed on logout — the device record persists with no
associated user (an "orphaned" device).

Operator scoping:
For operator-scoped tokens, only devices currently associated with a user
belonging to the token's operator are returned. Orphaned devices are excluded
because the operator that registered the device is no longer resolvable after
logout. Devices whose associated user has been soft-deleted ARE returned for
the operator they belonged to — the soft-deleted-user signal is preserved for
fraud-detection workflows. Applying filter[operatorId] follows the same rule.

Results are paginated using cursor-based pagination. By default they are
ordered by device ID descending (newest devices first); use the sort
parameter to override this order.