Fix Hetzner server redirect in onboarding flow

When creating a Hetzner server from the onboarding view, the redirect
to the server details page was not working properly due to modal context.
The standard redirect() call doesn't handle navigation from within modals.

Changes:
- Add from_onboarding flag to ByHetzner component
- Use wire:navigate redirect when in onboarding mode
- Pass from_onboarding=true from boarding view

This ensures proper navigation to the newly created server page instead
of staying on the onboarding view.

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

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

resources/views/livewire/boarding/index.blade.php

@@ -191,7 +191,7 @@
                                                 </div>
                                             </div>
                                         </x-slot:content>
-                                        <livewire:server.new.by-hetzner :private_keys="$this->privateKeys" :limit_reached="false" />
+                                        <livewire:server.new.by-hetzner :limit_reached="false" :from_onboarding="true" />
                                     </x-modal-input>
                                 @endif
                             @endcan