Fix 8 issues from code review

- ha-poller: replace recursive main() retry with while loop (stack overflow fix)
- ha-poller: advance last_push on empty HA response (log spam fix)
- ha-poller: use datetime.now(timezone.utc) instead of deprecated utcnow()
- ping-probe: always call update_status() unconditionally so offline devices register as offline
- agent.php: heartbeat reads status from payload instead of hardcoding 'online'
- phone-probe: delegate JSON building to python3 (bash concatenation injection fix)
- netscan + phone-probe: read registration key from /etc/jarvis-agent/reg-key
- admin/index.php: sync ha_list skipDomains with ha.php (14 missing domains added)
- facts_collector: self-check JARVIS via 127.0.0.1 instead of Cloudflare hairpin

api/endpoints/agent.php

@@ -111,7 +111,8 @@ switch ($agentAction) {
 
     // ── HEARTBEAT ────────────────────────────────────────────────────────────
     case 'heartbeat':
-        update_agent_seen($agent['agent_id'], 'online', trim($data['version'] ?? '') ?: null);
+        $hbStatus = in_array($data['status'] ?? '', ['online','offline']) ? $data['status'] : 'online';
+        update_agent_seen($agent['agent_id'], $hbStatus, trim($data['version'] ?? '') ?: null);
 
         // Return any pending commands for this agent
         $commands = JarvisDB::query(