fix: add null/false guards, proper error handling, and VNC popup fix

- Add isset() guards before count() on ipv4/ipv6 arrays in ServerResource
  to prevent PHP 8.0+ TypeError
- Add null checks after getWhmcsService() and getCP() in 18 Module methods
  and 5 ModuleFunctions methods to prevent fatal null dereference errors
- Add null guards for $whmcsService and $cp in admin.php impersonateServerOwner
- Fix HTTP status codes throughout admin.php (404, 400, 500, 502 instead of 200)
- Guard ConfigureService methods against $this->cp === false
- Use null coalescing for customfields access in initServerBuild
- Check API response code in initServerBuild instead of always returning true
- Replace exit() with RuntimeException in Curl.php
- Change catch(Exception) to catch(Throwable) in hooks.php for PHP 8.0+
- Open VNC window before AJAX call to avoid popup blocker

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

modules/servers/VirtFusionDirect/templates/js/module.js

@@ -466,6 +466,9 @@ function vfOpenVnc(serviceId, systemUrl) {
     spinner.show();
     alertDiv.hide();
 
+    // Open window immediately in click context to avoid popup blockers
+    var vncWindow = window.open("", "_blank");
+
     $.ajax({
         type: "GET",
         dataType: "json",
@@ -474,25 +477,28 @@ function vfOpenVnc(serviceId, systemUrl) {
         if (response.success && response.data) {
             var data = response.data.data || response.data;
             if (data.url) {
-                window.open(data.url, "_blank");
+                vncWindow.location.href = data.url;
             } else if (data.host && data.port) {
                 // Build noVNC URL if available
                 var vncUrl = "https://" + data.host + ":" + data.port;
                 if (data.token) {
                     vncUrl += "?token=" + encodeURIComponent(data.token);
                 }
-                window.open(vncUrl, "_blank");
+                vncWindow.location.href = vncUrl;
             } else {
+                vncWindow.close();
                 alertDiv.removeClass("alert-danger").addClass("alert-success");
                 alertDiv.text("VNC session is ready. Check your VirtFusion control panel for access.");
                 alertDiv.show();
             }
         } else {
+            vncWindow.close();
             alertDiv.removeClass("alert-success").addClass("alert-danger");
             alertDiv.text(response.errors || "VNC console is not available.");
             alertDiv.show();
         }
     }).fail(function () {
+        vncWindow.close();
         alertDiv.removeClass("alert-success").addClass("alert-danger");
         alertDiv.text("An error occurred. The server may be powered off.");
         alertDiv.show();