Save this content to: .cursor/rules/php-code.mdc

# PHP Code Style — Composer Plugin

## Mandatory Header

Every PHP file starts with `declare(strict_types=1)`.

## Classes

- `final readonly class` for: value objects (`SyncContext`), resolvers
- `final class` (without `readonly`) for: `AiRulesInstaller`, `Plugin`
- `Plugin` is `final class` — Composer instantiates with no args, optional constructor params for tests

## Typing

- All parameters, return types, and properties must be typed
- No `mixed` except with a comment justifying why
- PHPStan level 9: `@param list<string>` for skill name lists
- Nullable optional params: `?SyncContextResolverInterface $contextResolver = null`
- Return `?SyncContext` from resolver

## Constructor Patterns

```php
final readonly class DefaultSyncContextResolver implements SyncContextResolverInterface
{
    public function __construct(
        private string $packageName,
    ) {
    }
}
```

Plugin (tests may inject resolver/installer):

```php
public function __construct(
    ?SyncContextResolverInterface $contextResolver = null,
    ?AiRulesInstaller $installer = null,
) {
    $this->contextResolver = $contextResolver ?? DefaultSyncContextResolver::forBundleAiKit();
    $this->installer = $installer ?? new AiRulesInstaller();
}
```

## Language Features

- Native function prefix: `\is_dir()`, `\mkdir()`, `\copy()`, etc.
- Early return, trailing commas in multiline

## Namespace Organization

- `Contract/` — `SyncContextResolverInterface`
- `Context/` — `SyncContext`, resolver, `SkillNamesDiscoverer`
- `Installer/` — `AiRulesInstaller`
- Root — `Plugin` only

## Forbidden

- `new ConcreteService()` outside Plugin constructor (except tests)
- Setter injection
- `@phpstan-ignore` without comment

## After Every Change

`make cs-fix` then `make phpstan`