Implement App Localization (English, and possibly Finnish)

[brylie]

Here's a GitHub issue to focus on implementing localization with English and Finnish support:
To enhance user experience, we'll implement localization support using Flutter's intl package. This issue focuses on the initial setup and providing translations for English and Finnish.

Tasks:

• Project setup:
  • Add the flutter_localizations dependency to pubspec.yaml.
  • Initialize localization delegates within your MaterialApp widget.
• Extract localizable strings:
  • Identify all text elements within the app that require translation (button labels, instructions, etc.).
  • Wrap these strings with appropriate localization widgets (e.g., Text or custom widgets).
• Generate ARB files:
  • Use the Flutter localization tools to generate ARB (Application Resource Bundle) files. These will serve as the base for translations.
• OPTIONALLY: Provide Finnish translations:
  • Create ARB files for the Finnish language (e.g., intl_fi.arb).
  • Translate the extracted strings into Finnish, ensuring cultural appropriateness.
• Test and integrate:
  • Test the translations by switching the device's locale settings to Finnish. Verify correct display and any layout adjustments needed.

Additional Considerations:

• Language switcher: If applicable, implement a UI element to allow users to select their preferred language within the app.
• Date/Time Formatting: Utilize the intl package for locale-specific formatting of dates, times, and numbers (e.g. in the CSV export)
• External translation: Consider a process for professional or community-driven translation if you want to support additional languages in the future.

Benefits:

• Wider reach: Opens the application to a Finnish-speaking audience, increasing accessibility.
• Improved user experience: Provides a tailored experience for users based on their language preference.