Corrected the property access from array syntax to object syntax for `$hash->field` in the `CompletionChecker.php` file. This ensures proper handling of fields and prevents potential runtime errors.
Updated all Dockerfile stage names to adhere to a consistent lowercase naming convention with underscores. This improves readability and aligns with best practices for naming Docker build stages.
This commit ensures a writable .composer directory is created with appropriate permissions. This change resolves potential permission issues when using Composer inside the container.
