fix: Upgrade secure storage

[johannesvedder]

This pull request includes several updates across the Android, iOS, and Flutter common modules, focusing on upgrading dependencies, updating environment configuration, and aligning build settings with newer standards.

Build system and dependency upgrades:

• Upgraded Android build configuration to use Java 17 for both sourceCompatibility, targetCompatibility, and kotlinOptions.jvmTarget in app/android/app/build.gradle.kts. This modernizes the build environment and enables usage of newer Java features.
• Updated the flutter_secure_storage dependency to version ^10.0.0 in flutter_common/pubspec.yaml, allowing access to bug fixes and new features in the latest releases.
• Removed commented-out options in the FlutterSecureStorage initialization in flutter_common/lib/src/utils/storage.dart for cleaner and more maintainable code.

Configuration and environment changes:

• Updated the STUDYU_SUPABASE_PUBLIC_ANON_KEY value in the development environment file flutter_common/lib/envs/.env.dev, likely for security or access reasons.

Platform-specific settings:

• Removed the MinimumOSVersion key from the iOS AppFrameworkInfo.plist, possibly to inherit the default or configure it elsewhere.

Other minor changes include a formatting adjustment in the German localization Dart file, which does not affect functionality.

[github-actions]

Visit the preview URL for this PR (updated for commit 130754c):

• https://studyu-dev-app--pr804-fix-upgrade-secure-s-ojophc6j.web.app
• https://studyu-dev-designer--pr804-fix-upgrade-secure-s-l64j5d79.web.app

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[mohiuddinshahrukh]

I tested this locally:

• flutter_common tests passed.
• App web debug build passed.
• Android debug APK build passed.
• I completed the participant flow.
• Refreshing the dashboard preserved the active study state.

So other that one thing, everything looks good!