fix(settings): fix 404 on /settings for root user on cloud instance

- Make Server property nullable in Settings components (Index, Advanced, Updates)
- Add conditional server loading: only load when not on cloud
- Add null checks before using server for DNS validation and proxy configuration
- Fix isInstanceAdmin() to check root team's pivot role directly instead of current team
- Make root team (id=0) bypass subscription check on cloud
- Remove isInstanceAdmin() from main middleware bypass: only settings/admin routes are exempted
- Update isSubscribed() to only check isSubscriptionActive() for navbar consistency

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

app/Livewire/Settings/Updates.php

@@ -12,7 +12,7 @@ class Updates extends Component
 {
     public InstanceSettings $settings;
 
-    public Server $server;
+    public ?Server $server = null;
 
     #[Validate('string')]
     public string $auto_update_frequency;
@@ -25,7 +25,9 @@ class Updates extends Component
 
     public function mount()
     {
-        $this->server = Server::findOrFail(0);
+        if (! isCloud()) {
+            $this->server = Server::findOrFail(0);
+        }
 
         $this->settings = instanceSettings();
         $this->auto_update_frequency = $this->settings->auto_update_frequency;
@@ -76,7 +78,9 @@ class Updates extends Component
             }
 
             $this->instantSave();
-            $this->server->setupDynamicProxyConfiguration();
+            if ($this->server) {
+                $this->server->setupDynamicProxyConfiguration();
+            }
         } catch (\Exception $e) {
             return handleError($e, $this);
         }