Dynamic analysis for Auth calls

Fixes #184

In this PR I added 3 handlers handlers that provide types for the following cases:

// Request
$request->user();
$request->user('guard-name');

// Auth
Auth::user();

// Guard
Auth::guard('guard-name')->user();

and some other less often used.

TODO:

[ ] Add tests (can be tricky as I need to load custom auth.php config, any help is very welcome)
[ ] Consider use template syntax for Guard to infer type like:
```
$guard = Auth::guard('guard-name');
```

return $guard->user();



______

Previous implementation attempts:
 - https://github.com/psalm/psalm-plugin-laravel/pull/217

psalm / psalm-plugin-laravel