MongoDB Adapter for livedb / sharedb

livedb-mongo is a database adapter for `livedb` and its successor, `sharedb`, providing persistent storage and an oplog implementation using MongoDB. While historically named `livedb-mongo`, the project's development has transitioned to primarily support `sharedb`, with its GitHub repository now `sharedb-mongo`. The package is currently at v5.1.0 and maintains an active release cadence, frequently updating to support newer Node.js and MongoDB versions. It stores document snapshots directly in named collections and operations in `COLLECTION_ops`, enabling direct MongoDB queries against the unwrapped JSON documents, which include internal versioning fields (`_v`, `_type`). This adapter is crucial for enabling real-time collaborative applications built with `livedb` or `sharedb`, ensuring operational transformation (OT) works correctly with MongoDB as the backend. It explicitly warns against direct database manipulation outside of the `livedb`/`sharedb` API to prevent data corruption.