6.0
This commit aligns the project with IzzyOnDroid's reproducible builds guidelines:
- Enabled automatic BuildConfig generation and removed manual BuildConfig.java.
- Explicitly enabled vcsInfo in release build to include commit metadata in APK.
- Implemented optional signing configuration using keystore.properties.
- Disabled non-deterministic PNG crunching and vector PNG generation.
- Added BUILD_INSTRUCTIONS.md for verification builders.
- Corrected namespace and added .gitignore.
- Bumped versionCode to 6 and versionName to 0.6.0.