fix: remove seeded default users

[vickymaulana]

Motivation

• Prevent creation of a predictable privileged account during php artisan db:seed by removing seeded demo users so setup does not ship a known superadmin credential.

Description

• Deleted the code that created the Super Admin and Test User entries from database/seeders/DatabaseSeeder.php so the seeder now only runs SettingSeeder and RolePermissionSeeder.
• Removed the now-unused App\Models\User import from DatabaseSeeder.php as part of the cleanup.

Testing

• Ran php -l database/seeders/DatabaseSeeder.php which reported no syntax errors.
• Attempted php artisan test but it was skipped in this environment because vendor/autoload.php is missing, so the test suite could not be executed here.

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Codex Task