Adds 8 tests targeting AgentChannel branches missed by existing tests:
- resolve_any_stuck_down_alerts: device_down and device_up stuck alerts
resolved on next successful poll
- handle_in result with :PING job_type (deprecated SnmpResult path used
by older agents) creates a monitoring check without crashing
- handle_live_poll_result with malformed job_id (missing reply_topic)
hits the warning catch-all branch
- build_mikrotik_job is included in the initial dispatch when the device
has a discovered SNMP profile whose manufacturer is MikroTik or whose
sys_descr mentions RouterOS, and excluded when mikrotik_enabled is false
- process_additional_polling_data path with extra OIDs runs without
crashing the channel
Graham McIntire
bf2ad4031b