fix: Add explicit relativePathHelper argument to fix DI injection error

Fixes #31

Some environments fail to autowire the relativePathHelper argument when
other arguments are explicitly specified. This adds the explicit argument
to ensure consistent DI resolution across all environments.

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Co-Authored-By: Claude <[email protected]>

Author: yamadashy

extension.neon

@@ -15,6 +15,7 @@ services:
     errorFormatter.friendly:
         class: Yamadashy\PhpStanFriendlyFormatter\FriendlyErrorFormatter
         arguments:
+            relativePathHelper: @relativePathHelper
             simpleRelativePathHelper: @simpleRelativePathHelper
             lineBefore: %friendly.lineBefore%
             lineAfter: %friendly.lineAfter%