Added Mailpit setup and updated Keycloak configuration in local development runbooks. Improved Docker Compose stability with updated service dependencies and configurations. Archived outdated journal entries and documents for better organization.
Added `/ping/sync` endpoint with timestamp-based Delta-Sync functionality to efficiently support offline-first clients. Extended `PingApi` and frontend clients (`PingApiClient`, `PingApiKoinClient`) with `syncPings`. Updated repository, service, and controller logic for sync handling, including new JPA query `findByCreatedAtAfter`. Adjusted test doubles and completed unit tests for backend and frontend alignment. Documented sync approach and API usage.
stefan