[AI] Improve Dynamic Type support across Scrabbdict UI

[sochalewski]

Summary

• Reworked the main Scrabbdict layout to better adapt to larger Dynamic Type sizes, including wider regular-width content, scalable search controls, scrollable result cards, and a more resilient search mode picker.
• Updated search, result, empty state, rack words, and settings views to use dynamic SwiftUI text styles instead of fixed font sizes.
• Improved accessibility labels and hints for search modes and language selection, including localized handling of the question mark placeholder.
• Fixed localized point noun formatting by resolving strings through the active locale bundle.
• Refined the Scrabble table background positioning and fading so it scales more consistently across screen sizes.
• Added a simulator-only Dynamic Type overlay for debug builds, shown only when the active size differs from the default .large.
• Refreshed App Store marketing image assets after the UI changes.
• Extended snapshot coverage to include .xxxLarge Dynamic Type variants and refreshed affected snapshot references.

Testing

• Updated Scrabbdict and Settings snapshot tests for light/dark mode, iPhone/iPad layouts, supported locales, and large/xxxLarge Dynamic Type sizes.