* feat(pps_capture): allow selecting GPS receiver by device ID
Add PPS_CAP_GPS_ID parameter to select which GPS receiver's data
is used for PPS timestamp correlation. Matches by device ID rather
than uORB instance index, which avoids dependence on instance ordering.
When set to 0 (default), uses the first available instance for
backward compatibility.
* docs(pps_capture): document PPS_CAP_GPS_ID for multi-GPS setups
* fix(pps_capture): use GPS_MAX_RECEIVERS constant and mark PPS_CAP_GPS_ID reboot-required
* sensors: add per-receiver GPS delay parameters
Add SENS_GPS{0,1}_DELAY params to vehicle_gps_position, following the
same device-ID matching pattern used for antenna offsets. Each receiver
can now have its own measurement delay relative to the IMU.
The delay is applied to timestamp_sample before blending. When PPS time
correction is active it takes priority over the parameter-based delay.
When a GPS driver already provides its own timestamp_sample the
per-receiver delay is not applied on top of it.
* fix(ekf2): remove EKF2_GPS_DELAY and perform param transation
* fix(param_translation): fix GPS param migration return values
Add missing return for EKF2_GPS_POS_Z and remove incorrect return for
EKF2_GPS_DELAY (1-to-many migration should not return PARAM_MODIFIED).
* fix(sensors,ekf2): rename pps_compensation and clarify delay default
* fix(ekf2): account for SENS_GPS*_DELAY in observation buffer sizing
* fix(docs): migrate EKF2_GPS_DELAY param
Hamish Willee