[Kotlin Migration] FlashCardsContract

[n1snt]

Checklist

• [x] You have not changed whitespace unnecessarily (it makes diffs hard to read)
• [x] You have a descriptive commit message with a short title (first line, max 50 chars).
• [x] Your code follows the style of the project (e.g. never omit braces in if statements)
• [x] You have commented on your code, particularly in hard-to-understand areas
• [x] You have performed a self-review of your own code
• [ ] UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• [ ] UI Changes: You have tested your change using the Google Accessibility Scanner

[github-actions[bot]]

Hello 👋, this PR has been opened for more than 2 months with no activity on it. If you think this is a mistake please comment and ping a maintainer to get this merged ASAP! Thanks for contributing! You have 7 days until this gets closed automatically

[david-allison]

Superseded by https://github.com/ankidroid/Anki-Android/pull/12232