Adds scripts/sync-android-version.mjs which writes versionName (semver) and a
monotonic versionCode (major*10000+minor*100+patch) into android/app/build.gradle
from package.json. Wired into `npm run android:build` and `android:sync`, plus a
standalone `npm run android:version`. Now you bump ONE number (package.json) and
never hit Zapstore's "already exists" again. Exits quietly if android/ isn't
generated yet.
Co-authored-by: shakespeare.diy <assistant@shakespeare.diy>
