Fix iOS crash when importing decks from clipboard

[NickDeVeau]

Summary

• avoid the iOS/RoboVM crash caused by named capture groups in the deck import regexes
• preserve named-group behavior on standard JVMs while falling back to indexed capture groups on regex engines that reject the syntax
• cover every importer pattern and a representative sideboard/card line with a portability regression test

Root cause

Opening Import from Clipboard initializes DeckRecognizer. RoboVM's regex implementation rejects Java named capture syntax such as (?<pre>...), which raised a PatternSyntaxException during static initialization and terminated the iOS app with an ExceptionInInitializerError.

Testing

• focused Maven regression test passed for DeckRecognizerPortablePatternTest
• iOS IPA built successfully in GitHub Actions
• installed and verified on a physical iPad running iPadOS 18.7.3
• confirmed the original clipboard import crashed before the change and imports successfully afterward

Contribution note

The issue was reproduced and the fix was validated on-device by the contributor. OpenAI Codex assisted with diagnosis, implementation, test creation, and PR preparation.

[tool4ever]

This seems to be the same cause as #8976
so I assume it could crash on Android too

While this does add some overhead I wouldn't mind having this transformation done via code, as simply refactoring this class into indexes too might be a more messy alternative?