Enhancement: Bump compileSdk and targetSdk to API 35 (Android 15)

[github-actions]

Summary

The project currently targets Android 14 (API 34). Android 15 (API 35) is now stable and Google Play requires apps to target it by August 2025.

Motivation

• Apps targeting API 35 unlock Android 15 features (edge-to-edge enforcement, predictive back, photo picker improvements, health connect).
• Google Play's target API level policy requires apps to target API 35 by August 31, 2025 for updates to existing apps.
• Jetpack Compose components have improved behavior when targetSdk = 35 (e.g., better edge-to-edge inset handling).

Proposed Changes

1. In buildSrc/src/main/kotlin/.../ProjectConfigs.kt:

   const val compileSdkVersion = 35
   const val targetSdkVersion = 35

2. Ensure the Android Gradle Plugin version in build.gradle.kts supports SDK 35 (AGP 8.2.2 supports it; AGP 8.3+ recommended).
3. Test for any behavior changes introduced by targeting API 35:
   • Edge-to-edge is enforced by default on Android 15; ensure all screens handle window insets correctly using WindowInsets composables.
   • Verify the app handles the predictive back gesture where applicable.
4. Update the README badge which references an old Compose version.

References

• Android 15 Behavior Changes
• Google Play target API requirements