fix: skip password confirmation for OAuth users

OAuth users don't have passwords set, so they should not be prompted for password confirmation when performing destructive actions. This fix:
- Detects OAuth users via the hasPassword() method
- Skips password confirmation in modal for OAuth users
- Keeps text name confirmation as the final step
- Centralizes logic in helper functions for maintainability
- Changes button text to "Confirm" when password step is skipped

Fixes #4457

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

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

app/Livewire/Project/Database/BackupEdit.php

@@ -2,12 +2,9 @@
 
 namespace App\Livewire\Project\Database;
 
-use App\Models\InstanceSettings;
 use App\Models\ScheduledDatabaseBackup;
 use Exception;
 use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
-use Illuminate\Support\Facades\Auth;
-use Illuminate\Support\Facades\Hash;
 use Livewire\Attributes\Locked;
 use Livewire\Attributes\Validate;
 use Livewire\Component;
@@ -154,12 +151,8 @@ class BackupEdit extends Component
     {
         $this->authorize('manageBackups', $this->backup->database);
 
-        if (! data_get(InstanceSettings::get(), 'disable_two_step_confirmation')) {
-            if (! Hash::check($password, Auth::user()->password)) {
-                $this->addError('password', 'The provided password is incorrect.');
-
-                return;
-            }
+        if (! verifyPasswordConfirmation($password, $this)) {
+            return;
         }
 
         try {