React Native app: offline mode and push notifications

An existing React Native app (news reader for a media client) needs two features: robust offline reading and push notifications with topic subscriptions. Offline mode should download the day's articles and images for flight mode reading, with sensible cache eviction. Push uses Firebase Cloud Messaging; the backend endpoints exist already. The codebase is TypeScript, well tested, around 30k lines. We will onboard you with a walkthrough call and a staging environment. Please mention similar offline-sync work in your proposal.