Release 2.0.0

Breaking changes
- Increase minSdk to 28
- Maven group changed to com.github.BlueCodeSystems

New
- Modernize build toolchain: Gradle 8.7, AGP 8.6.0, Java 17
- Target modern Android: compileSdk 35, targetSdk 35, Build Tools 35.0.0
- Pin NDK via android.ndkVersion=26.2.11394342
- Add Maven Central publishing helpers (Central bundle zip + checksums)

CI/Publishing
- JitPack publishes to Maven Local (generates POM + artifacts)
- Disable signing on JitPack via -PskipSigning=true
- Derive GROUP from repository owner in jitpack.yml

Docs
- Update README with modernization details, JitPack flags, and install instructions