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.

app/Services/VultrService.php

@@ -153,19 +153,19 @@ class VultrService
 
     public function getInstance(string $instanceId): array
     {
-        $response = $this->request('get', "/instances/{$instanceId}");
+        $response = $this->request('get', $this->instanceEndpoint($instanceId));
 
         return $response['instance'] ?? [];
     }
 
     public function startInstance(string $instanceId): array
     {
-        return $this->request('post', "/instances/{$instanceId}/start");
+        return $this->request('post', $this->instanceEndpoint($instanceId).'/start');
     }
 
     public function deleteInstance(string $instanceId): void
     {
-        $this->request('delete', "/instances/{$instanceId}");
+        $this->request('delete', $this->instanceEndpoint($instanceId));
     }
 
     public function getInstances(): array
@@ -183,4 +183,9 @@ class VultrService
 
         return null;
     }
+
+    private function instanceEndpoint(string $instanceId): string
+    {
+        return '/instances/'.rawurlencode($instanceId);
+    }
 }