fix: update facts_collector for JARVIS VM (not DO web host)

- Site checks use external URLs instead of 127.0.0.1 loopback (JARVIS
  no longer shares a server with the websites)
- JARVIS site URL updated to port 1972
- Fixed syntax error in DO server ping exec call
- Removed Host header injection (not needed for external checks)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api/endpoints/do_server.php

@@ -39,7 +39,7 @@ foreach ($svcNames as $s) {
 
 // Site health from kb_facts
 $siteLabels = [
-    "jarvis"       => "jarvis.orbishosting.com",
+    "jarvis"       => "jarvis.orbishosting.com:1972",
     "tomsjavajive" => "tomsjavajive.com",
     "epictravelexp"=> "epictravelexpeditions.com",
     "parkersling"  => "parkerslingshotrentals.com",