🔥 Remove Laravel Sail, Docker, and related setup, migrate to simplified local development environment

- **Removed:** `docker-compose.yml`, Sail-specific Dockerfiles, and related scripts for PHP 8.3 setup.
- **Updated:** Documentation to reflect a shift from Docker to a direct PHP-based local development workflow.
- **Removed:** `laravel/sail` dependency from `composer.lock`.
- **Implemented:** `#[Locked]` Livewire attribute across components for read-only properties.
- **Added:** Feature tests to ensure locked properties cannot be tampered with.

phpunit.xml

@@ -25,7 +25,7 @@
         <env name="APP_MAINTENANCE_DRIVER" value="file"/>
         <env name="BCRYPT_ROUNDS" value="4"/>
         <env name="CACHE_STORE" value="array"/>
-        <env name="DB_DATABASE" value="testing"/>
+        <env name="DB_DATABASE" value="einundzwanzig_app_testing"/>
         <env name="MAIL_MAILER" value="array"/>
         <env name="PULSE_ENABLED" value="false"/>
         <env name="QUEUE_CONNECTION" value="sync"/>