#3 Add publish workflow

Summary by cubic

Automates publishing the Android library to Maven Central on tagged releases and configures Gradle/POM metadata for dev.wvb:webview-bundle-android. Adds consumer ProGuard rules to keep JNA/UniFFI classes so FFI works in minified apps.

• New Features

  • GitHub Actions workflow publishes on v* tags; derives version from tag and runs :lib:publishToMavenCentral with signing from secrets.
  • Integrates com.vanniktech.maven.publish (0.35.0); sets dev.wvb:webview-bundle-android, publishes sources/javadoc JARs, and fills POM metadata.

• Bug Fixes

  • Replace JS bridge keep rule with consumer rules for JNA/UniFFI to prevent R8 stripping/renaming of native bindings and avoid runtime FFI failures.