minipack3n: Initial config for sensor_service

Summary:
**Description**
Add sensor_service.json for the minipack3n sensor_service.
This configuration has been tested on minipack3.

**Differences**
Due to hardware differences in the SMB section between minipack3 and minipack3n,
sensor_service logs are expected to show errors related to SMB_VRM*.

**Test Plan**
- Run jq to format the json file.
- Run sensor_service with the updated config file is correct.
- Validate the generated logs to ensure functionality, excluding the known SMB_VRM-related errors.

[minipack3n_sensor_service_config_test_20250120.txt]
(https://github.com/user-attachments/files/18474587/minipack3n_sensor_service_config_test_20250120.txt)