Add standaloneLine set and Symfony attribute param fixer

[TomasVotruba]

Standalone-line Symfony attribute fixer + standaloneLine set

New fixer: StandaloneLineSymfonyAttributeParamFixer

Breaks each argument of a Symfony attribute onto its own line (detection: the written attribute name contains the Symfony namespace part). Third-party attributes keep their layout.

-#[\Symfony\Component\Console\Attribute\AsCommand(name: 'mautic:entity:import', description: 'Import entity data from a ZIP file.')]
+#[\Symfony\Component\Console\Attribute\AsCommand(
+    name: 'mautic:entity:import',
+    description: 'Import entity data from a ZIP file.'
+)]
 final class SomeCommand
 {
 }

Skipped: attributes without arguments (#[\Override]), empty argument lists, and non-Symfony attributes (e.g. #[\Doctrine\ORM\Mapping\Table(...)]).

New standaloneLine set

Opt-in set grouping the standalone-line rules:

• StandaloneLineSymfonyAttributeParamFixer (new)
• StandaloneLinePromotedPropertyFixer
• StandaloneLinePlainConstructorParamFixer
• StandaloneLineRequiredParamFixer

Usage:

$ecsConfig->withPreparedSets(standaloneLine: true);
// or
$ecsConfig->withSets([SetList::STANDALONE_LINE]);

Wired via SetList::STANDALONE_LINE and a new withPreparedSets(standaloneLine: ...) flag. Not part of the common aggregate — enable explicitly.

Moved rule

StandaloneLinePlainConstructorParamFixer removed from the spaces set (SpacesLevel::RULES); it now lives in the new standaloneLine set.