feat: introduce new rule to fix var comment

[94noni]

Warning

WIP, just to make stuff rolling on my side

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close #375

• https://twig.symfony.com/doc/3.x/tags/types.html
• https://speakerdeck.com/fabpot/symfonycon-vienna-2025-twig-still-relevant-in-2025?slide=25

this PR introduce a new rule to fix comment var comment declaration to the new types tag

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for now I am trying mostly to understand the project itself and token parsing etc
feel free to comment nonetheless

[VincentLanglet]

Hope it helps

Feel free to ask anything about how twig-cs-fixer works

[VincentLanglet]

COMMENT_START_TYPE is always {#

if (!$this->isTokenMatching($token, Token::COMMENT_START_TYPE)) {
     return;
}

$nextText = $tokens->findNext([Token::COMMENT_TEXT_TYPE,  Token::COMMENT_END_TYPE], $tokenIndex);
Assert::notFalse($nextText, 'Closing tag cannot be null.');
$nextTextToken = $tokens->get($nextText);
if (!$nextTextToken->isMatching(Token::COMMENT_TEXT_TYPE, '@var') {
    return;
}

$fixer = $this->addFixableError(
            'Variable comment declaration must be used via types tag instead of comment.',
            $token
);
if (null === $fixer) {
      return;
}

// Then do the fix

$end = $tokens->findNext(Token::COMMENT_END_TYPE, $nextText);
Assert::notFalse($nextText, 'Closing tag cannot be null.');

// You might look for varName and varType before adding the fixable error because you don't want to report an error for something like
// `{# @var #}` or `{# @var foo #}`
$varName = ...;
$varType = ...;

// We will have to handle things like 
// `{# @var foo App\Foo\Bar some comments to explain things #}`
$comment = ...;