fix(release): enforce Android version parity (#141)

Adds a deterministic metadata guard before CI and F-Droid builds so generated release artifacts cannot silently inherit stale Gradle versions.\n\nPlan: https://github.com/dzianisv/opencode-mobile/issues/95#issuecomment-5047827673

Co-authored-by: engineer <engineer@gray-knight-m1.local>

package.json

@@ -9,6 +9,7 @@
     "ios": "expo run:ios",
     "android": "expo run:android",
     "typecheck": "tsc --noEmit",
+    "check:versions": "node scripts/check-version-parity.mjs",
     "test": "node --test 'src/**/*.test.ts'"
   },
   "dependencies": {