Implement comprehensive localization framework with English and Finnish support

- Add flutter_localizations dependency and l10n configuration
- Create ARB files for English (en) and Finnish (fi) translations
- Localize UI strings across all major components:
  * Navigation drawer and page titles
  * Scoring interface (arrows per end, ruleset names)
  * Scorecard headers (End, Arrows, Sum of 3/6, Accumulative)
  * Keypad functional buttons (CLEAR/TYHJENNÄ, CLOSE/SULJE)
  * Settings page placeholder content
  * Dialog messages and confirmation prompts
- Preserve universal archery scoring notation (X, 10, 9, M remain unlocalised)
- Use authentic Finnish archery terminology throughout
- Configure main app with proper localization delegates and supported locales
- Generate localization classes automatically via flutter_localizations

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

pubspec.yaml

@@ -30,6 +30,9 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
+  flutter_localizations:
+    sdk: flutter
+    # flutter_localizations should automatically get the correct intl version
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
@@ -63,6 +66,9 @@ flutter:
   # included with your application, so that you can use the icons in
   # the material Icons class.
   uses-material-design: true
+  
+  # Enable code generation for localization
+  generate: true
 
   # To add assets to your application, add an assets section, like this:
   # assets: