fix(ci): use production APP_VARIANT for release APK build

The preview EAS profile was setting APP_VARIANT=preview, causing the
Android package to be com.readany.app.preview instead of
com.readany.app. This made the release APK install as a separate app.
Override with APP_VARIANT=production in the CI env so the correct
production identifier is used.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: bealqiu

.github/workflows/release.yml

@@ -113,6 +113,7 @@ jobs:
       - name: Build Android APK (Local)
         env:
           EXPO_PUBLIC_FEEDBACK_WORKER_URL: ${{ secrets.FEEDBACK_WORKER_URL }}
+          APP_VARIANT: production
         run: |
           VERSION=${GITHUB_REF_NAME#v}
           cd packages/app-expo