fix(vultr): validate public network and token scope

Require IPv6 when public IPv4 is disabled, constrain cloud token
lookup by team and provider during deletion, and encode Vultr instance IDs
in API paths.

resources/views/livewire/security/cloud-provider-token-form.blade.php

@@ -33,7 +33,7 @@
                 @if ($provider === 'vultr')
                     Open Account → API Access.
                     <br><br>
-                    Don't have a Vultr account? <a href='https://www.vultr.com/register-steps/' target='_blank'
+                    Don't have a Vultr account? <a href='https://www.vultr.com/?ref=9911335' target='_blank'
                         class='underline dark:text-white'>Sign up here</a>
                     <br>
                     <span class="text-xs">Coolify's affiliate link, only new accounts - supports us</span>
@@ -74,7 +74,7 @@
                     @if ($provider === 'vultr')
                         Open Account → API Access.
                         <br><br>
-                        Don't have a Vultr account? <a href='https://www.vultr.com/register-steps/' target='_blank'
+                        Don't have a Vultr account? <a href='https://www.vultr.com/?ref=9911335' target='_blank'
                             class='underline dark:text-white'>Sign up here</a>
                         <br>
                         <span class="text-xs">Coolify's affiliate link, only new accounts - supports us</span>